Genetic analysis of phenotypic variation for ectomycorrhiza formation in an interspecific F1 poplar full-sib family.

A plant's capability to develop ectomycorrhizal symbiosis is under the control of both genetic and environmental factors. In order to determine the roles played by these different factors, we have performed a quantitative genetic analysis of the ability of poplar trees to form ectomycorrhizas. Quantitative genetics were applied to an interspecific family of poplar for which the two parental genetic maps had already been described, and for which data analyses concerning fungal aggressors were obtained. Quantitative trait loci (QTL) related to ectomycorrhiza formation were identified and located in the genetic maps of the two parents. One QTL was located at a linkage group of the genetic map of Populus trichocarpa showing a high concentration of several QTL involved in the pathogenic interaction with the fungus Melampsora larici-populina, the causal agent of leaf rust.

Homolateral ataxia and crural paresis: a crossed cerebral-cerebellar diaschisis.

A patient developed weakness of the right leg and homolateral ataxia of the arm, caused by a subcortical infarct in the area supplied by the anterior cerebral artery in the left paracentral region, demonstrated by CT and MRI. Cerebral blood flow studied by technetium-labelled hexamethyl-propylene-amine oxime using single photon emission computed tomography showed decreased blood flow in the left lateral frontal cortex and in the right cerebellar hemisphere ("crossed cerebral-cerebellar diaschisis"). The homolateral ataxia of the arm may be caused by decreased function of the right cerebellar hemisphere, because of a lesion of the corticopontine-cerebellar tracts, whereas crural hemiparesis is caused by a lesion of the upper part of the corona radiata.

So-called generalized epilepsy in children leading to frontal epilepsy with a frontal syndrome in adulthood: a clinical, EEG and radiological study of 10 cases.

The authors report 10 cases of epileptic patients with the onset in childhood of the clinical and EEG features of cryptogenic generalized epilepsy which evolved into frontal epilepsy, confirmed by the clinical and EEG features and was associated with a frontal syndrome. CT-scan and MRI showed mild atrophy in the frontal area, while SPECT showed a decrease in the frontal blood flow in 70% of the cases. The authors consider that frontal epilepsy may mimic generalized epilepsy.

[Transient neurologic deficit preceding intracerebral hemorrhage. Physiopathological hypotheses]. / Déficits neurologiques transitoires précédant les hémorragies intraparenchymateuses. Hypothèses physiopathologiques.

Seventeen out of 238 cases (7%) of intracerebral hemorrhage were preceded by transient neurological deficit. In two cases, intracerebral hemorrhage and transient neurological deficit were thought to be due to amyloid angiopathy, this diagnosis was confirmed at autopsy in one case. In one case, intracerebral hemorrhage and transient neurological deficit were due to a cavernoma. In the other 14 cases, hypertension was the major risk factor. In 3 of them, CT-scans made after the transient neurological deficit but before the intracerebral hemorrhage showed deep small hypodensities suggestive of lacunas. The mechanisms of transient neurological deficit preceding intracerebral hemorrhage are reviewed.

[Prognosis of transient ischemic accidents disclosing infarction]. / Pronostic des accidents ischémiques transitoires révélant un infarctus.

In a prospective study, thirty six out of 175 consecutive patients (21%) with transient ischemic attack (TIA), had cerebral infarction on CT-scan. This group of patients differed from the group without cerebral infarction by a higher age, a longer duration of neurological deficit, a greater frequency of neurological history, vertebro-basilar TIAs, cephalagia and, cardiac arrhythmia, and by a higher 2-year mortality rate. Due to their difference in etiological factors and prognosis, TIAs with cerebral infarction on CT-scan should be differentiated from those without cerebral infarction.

[Natural history of lacunar syndromes. Contribution of the Dijon registry of cerebrovascular complications]. / Histoire naturelle des syndromes lacunaires. Apport du registre dijonnais des accidents vasculaires cérébraux.

In a consecutive series of 984 first-ever strokes (from 1985 to 1989) in a population based study, 165 (16.7%) had lacunar infarction confirmed by CT-scan or M.R.I. The annual incidence was 35.6/100,000 in women, and 47.8/100,000 in men. Survival rates were 90% at 1 month, and 78% at 2 years. The rate of recurrent strokes was 11% at 2 years. The natural history of lacunar infarction could be drawn in this study which was population-based; 29% of lacunar infarctions are indeed not managed in hospitals. Lacunar infarctions should be identified as such in therapeutic trials since their course is clearly different from other types of strokes.

[AIDS and myasthenia: an uncommon association]. / SIDA et myasthénie: une association exceptionnelle.

A 18 year-old soldier, heroin-addict, presented with the association of myasthenia gravis and HIV infection with a specific subacute encephalopathy. To our knowledge, it is the second reported case. This association may result from an immune dysregulation due to nonspecific thymic modifications, which has been reported in AIDS.

[Cerebral vascular complications in the population of Dijon. Incidence-breakdown-mortality]. / Les accidents vasculaires cérébraux dans la population dijonnaise. Incidence--Répartition--Mortalité.

Since 1985, a stroke registry has registered every stroke in this town, of about 140,000 inhabitants. A CT Scan and numerous sources of information have allowed to achieve an exhaustive survey. The annual incidence of stroke has been 145/100,000. The annual specific incidence for age is 170/100,000 in men, 126/100,000 in women. The annual specific incidence for age and sex has shown a female preponderance until 30 and a male preponderance after this age. At 80, the rates became equal. Sixty-eight per cent of stroke were due to an infarct, 12 p. 100 to lacunae, 5 p. 100 to subarachnoid hemorrhage and 15% to cerebral hemorrhage. A preponderance of young people was found in subarachnoid hemorrhage, of the fifth decade in cerebral hemorrhage, while infarct rose up with age in the 2 sexes. Infarcts appeared predominantly during winter, while transient ischemic attacks appeared more often during summer. Cerebral hemorrhage had a constant incidence over the year. Mortality was high, mainly during the first month with 12.5 p. 100 during the first week, 21.5 p. 100 during the first month, and 30 p. 100 the first year. Our results appear to set in the mean of white occidental countries as opposed to Japan. They emphasize the important and underestimated place of lacunae and the seasonal variations of several causal varieties of stroke.

Stroke in a French prospective population study.

Since 1985 there has been a Stroke Registry in Dijon to record every stroke occurring in the population of a city of 140,000 inhabitants. The survey has been exhaustive and included the numerous sources of information as well as CT scanning. The annual incidence is 145/100,000 with an annual specific incidence of 170/100,000 in men, 126/100,000 in women. The annual specific incidence shows a female preponderance until 30 years of age, after which the males lead from the age of 30 to 80, when the rates become equal. Sixty-eight percent of strokes produced by infarct, 12% by lacunae, 5% by subarachnoid hemorrhage and 15% by cerebral hemorrhage. Differences exist in this distribution, with the preponderance of young people in subarachnoid hemorrhage, and cerebral hemorrhage is commoner in the 5th decade while infarct increases with age in both sexes. Infarct appears commoner during winter, transient ischemic attacks during summer, while cerebral hemorrhage has a constant incidence during the year. Mortality is high mainly during the 1st month with 12.5% during the 1st week, 21.5% the 1st month and 30% the 1st year. Our results are in the mean similar to white occidental countries, but opposite to those observed in Japan; they emphasize the importance of the lacunar syndrome, and the seasonal variations in different types of stroke.

[Incidence of cerebrovascular accidents in a medium-sized French town]. / Incidence des accidents vasculaires cérébraux dans une ville française moyenne.

Beginning in 1985, the Dijon Stroke Registry has identified every case of stroke occurring in this city of 140,000 inhabitants. The systematic use of a CT scan and multiple other sources of information ranging from hospital doctors to general practitioners make it possible for us to have virtually exhaustive data on stroke incidence. The gross incidence was 170 per 100,000 among men and 126 per 100,000 among women. Specific incidence by age and sex shows female predominance up to 30 years of age, and male predominance among victims from 30 to 80 years old. Beyond 80, rates were identical for both sexes. In 68% of the cases, the strokes were caused by infarct; in 12%, by lacunae; in 15%, by cerebral hemorrhage; in 5%, by subarachnoid hemorrhage. Significant differences existed in this distribution according to age, with a clear predominance of young people among those having subarachnoid hemorrhage, while, for those over 40, cerebral hemorrhages were frequent; the proportion of infarct increased with age for both sexes. A peak of incidence for infarct appeared during winter, while transient ischemic accident was more frequent in summer. Cerebral hemorrhage had a similar incidence throughout the year. Mortality was high during the first month (12.5% during the first week, 21.5% during the first month), and reached 30% during the first year. These results are comparable to those generally observed among white occidental populations. They confirm the limited incidence of hemorrhages (contrary to what has been observed in Japan), emphasize the important and often underestimated role of lacunar syndromes, and the seasonal variations specific to each mechanism.