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C Thomas-Anterion

Publications and source records attributed to C Thomas-Anterion.

9 recordsLinked to original sources

Apolipoprotein E epsilon4 allele and familial aggregation of Alzheimer disease.

OBJECTIVE: To investigate the relationship among risk for Alzheimer disease (AD), familial aggregation of AD, and the apolipoprotein E (apoE) epsilon4 allele in first-degree relatives of probands with AD and known apoE genotype. PATIENTS: Two hundred ninety subjects fulfilling the criteria of the National Institute of Neurological Communicative Disease and Stroke-Alzheimer's Disease and Related Disorders Association for probable AD were ascertained from March 1, 1992, to December 31, 1996, through consecutive admissions in several university hospitals. DESIGN AND METHODS: Family data were collected on 1176 first-degree relatives (parents and siblings), aged 40 to 90 years. Most living relatives underwent a clinical examination, whereas we relied on family history for clinical data for deceased or unavailable relatives. First, we conducted standard survival analyses to estimate cumulative lifetime risk (LTR) for AD among relatives and to investigate for sex and apoE genotype effects on LTR. Then, we assessed to what extent clustering of secondary AD could be explained by the apoE epsilon4 allele by deriving the expected proportions of relatives with 0, 1, or 2 apoE epsilon4 alleles conditionally on the proband's genotype. RESULTS: Cumulative LTR for AD among first-degree relatives increased significantly with the number of epsilon4 alleles present in the proband. By 90 years of age, LTRs in relatives of probands with epsilon3/epsilon3, epsilon3/epsilon4, and epsilon4/epsilon4 genotypes were 29.2%, 46.1%, and 61.4%, respectively. Significant sex-by-apoE genotype interaction effects on LTR were observed. Women had about a 2-fold higher risk for AD than men among relatives of epsilon4 carriers but not among relatives of non-epsilon4 carriers. The predicted proportion of epsilon4 carriers in relatives of probands with epsilon3/epsilon3 genotype remains about 50% lower than the corresponding LTR for AD, indicating that familial clustering of AD is largely due to other factors than the apoE epsilon4 allele. Although aggregation of AD in families of probands with the epsilon4 allele is more prominent, we estimated that AD would not develop in about 30% of female and up to 60% of male relatives carrying at least 1 epsilon4 allele, even by 90 years of age. CONCLUSION: Our results support the hypothesis that the apoE epsilon4 allele enhances AD susceptibility, but putative factors enhancing risk for AD remain to be found.

Adult

[Memory and dementia].

Memory impairment in ageing is clearly different from Alzheimer's disease. Many papers dealed with the modifications of the different cognitive sections of memory at different stages of Alzheimer's progression: the early involvement of working and episodic memories, those later of semantic and retrograde memories and the lasting saving of implicit memory must be know by clinicians to better understand the target of symptomatic therapy and to differentiate Alzheimer from others degenerative dementias. Above all, these progress authorize an early diagnostic of "possible Alzheimer" at a pre-dementia stage facing to isolated memory complaint. The amnesic profile of others dementias is different and the qualitative approach of testing become essential for the categorization of dementias at early stages with an isolated progressive memory disorder.

Alzheimer Disease

Apolipoprotein E and Alzheimer disease: genotype-specific risks by age and sex.

The distribution of apolipoprotein E (APOE) genotypes as a function of age and sex has been examined in a French population of 417 Alzheimer disease (AD) patients and 1,030 control subjects. When compared to the APOE epsilon3 allele, an increased risk associated with the APOE epsilon4 allele (odds ratio [OR] [epsilon4] = 2.7 with 95% confidence interval [CI] = 2.0-3.6; P < .001) and a protective effect of the APOE epsilon2 allele (OR[epsilon2] = 0.5 with 95% CI = 0.3-0.98; P = .012) were retrieved. An effect of the epsilon4 allele dosage on susceptibility was confirmed (OR[epsilon4/epsilon4] vs. the epsilon3/epsilon3 genotype = 11.2 [95% CI = 4.0-31.6]; OR[epsilon3/epsilon4] vs. the epsilon3/epsilon3 genotype = 2.2 [95% CI = 1.5-3.5]). The frequency of the epsilon4 allele was lower in male cases than in female cases, but, since a similar difference was found in controls, this does not lead to a difference in OR between sex. ORs for the epsilon4 allele versus the epsilon3 allele, OR(epsilon4), were not equal in all age classes: OR(epsilon4) in the extreme groups with onset at < 60 years or > 79 years were significantly lower than those from the age groups 60-79 years. In epsilon3/epsilon4 individuals, sex-specific lifetime risk estimates by age 85 years (i.e., sex-specific penetrances by age 85 years) were 0.14 (95% CI 0.04-0.30) for men and 0.17 (95% CI 0.09-0.28) for women.

Age of Onset

Segregation analysis of Alzheimer pedigrees: rare Mendelian dominant mutation(s) explain a minority of early-onset cases. French Alzheimer Collaborative Group.

Segregation analysis of Alzheimer disease (AD) in 92 families ascertained through early-onset ( < or = age 60 years) AD (EOAD) probands has been carried out, allowing for a mixture in AD inheritance among probands. The goal was to quantify the proportion of probands that could be explained by autosomal inheritance of a rare disease allele "a" at a Mendelian dominant gene (MDG). Our data provide strong evidence for a mixture of two distributions; AD transmission is fully explained by MDG inheritance in < 20% of probands. Male and female age-of-onset distributions are significantly different for "AA" but not for "aA" subjects. For "aA" subjects the estimated penetrance value was close to 1 by age 60. For "AA" subjects, it reaches, by age 90, 10% (males) and 30% (females). We show a clear cutoff in the posterior probability of being an MDG case.

Age Factors

[Preservation of procedural memory in 18 patients operated for aneurysm of the anterior communicating artery].

Organic amnesia is typically associated with lesions in either the diencephalic or medial temporal regions of the brain. However, amnesia can result from other kinds of lesions, in particular those resulting from an aneurysm of the anterior communicating artery (ACoA). In the present study, 7 patients who became amnesic following a ruptured and operated ACoA aneurysm were comparated neuropsychologically with 11 patients with ruptures but no cognitive complaints and 18 normal control subjects. They were submitted to explicit and implicit memory tests and to tests claimed to be sensitive to frontal lobe dysfunction. The performance of the 11 ACoa patients without cognitive complaints revealed evidence for a functional frontal dysfunction (test of Stroop) and a partial deficit of explicit memory (free recall and long-term recall). The performance of the 7 ACoa amnesics revealed evidence for a functional frontal dysfunction and a deficit of explicit memory (safe in recognition). Anosognosia was also observed. The performance of all patients revealed the preservation of implicit memory in procedural tasks (serial reaction time and mirror reading) as diencephalic and temporal amnesia. The functionnal nature of the syndrome is discussed.

Adult

Characteristics of familial aggregation in early-onset Alzheimer's disease: evidence of subgroups.

Characteristics of familial aggregation of Alzheimer's Disease were studied in 92 families ascertained through a clinically diagnosed proband with an onset below age 60 years. In each family data were systematically collected on the sibships of the proband, of his father, and of his mother. A total of 926 relatives were included and 81% of the living relatives (i.e., 251 individuals) were directly examined. The estimated cumulative risk among first degree relatives was equal to 35% by age 89 years (95% confidence interval 22 to 47%). This result does not support the hypothesis that an autosomal dominant gene, fully penetrant by age 90 years, is segregating within all these pedigrees. Despite the fact that all probands were selected for an onset before age 60 years it was shown that two types of families could be delineated with respect to age at onset among affected relatives: all secondary cases with an onset below age 60 years were contributed by a particular group of families (type 1 families), whereas all secondary cases with an onset after age 60 years were contributed by another group of families (type 2 families). Although genetic interpretation of these findings is not straightforward, they support the hypothesis of etiologic heterogeneity in the determination of early-onset Alzheimer's disease.

Adult

[Unexplained chronic diarrhea, apropos of 4 new cases under Cyclo 3 fort and review of the literature].

We report 4 cases of chronic diarrhoea in patients treated with Cylclo 3 fort. This side-effect was not mentioned in the French list of therapeutic drugs until 1992. The diarrhoea was without faeces and without glairy mucus or blood. Symptomatic treatments were totally ineffective. The diarrhoea itself was well tolerated, but 3 patients lost weight, with hypokalaemia in 2 of them, and 1 had regressive acute renal failure. The time elapsed between the first dose of Cyclo 3 fort and the diarrhoea ranged from 1 to 3 months, and it took 5 months to make the aetiological diagnosis. Two patients were hospitalized. Withdrawal of the drug always resulted in cure. One patient taking enemas developed a regressive subocclusion of the bowel. The physiopathological mechanism of this diarrhoea is unknown. These cases are similar to the 5 other cases reported in the literature.

Acute Kidney Injury