Search PubMed⌕ Search

Biomedical subjects

C Jeandel

Publications and source records attributed to C Jeandel.

At least 55 records · Page 3Linked to original sources

[Alzheimer disease, markers in the cerebrospinal fluid. Support of physiopathologic hypotheses].

CERTAIN DIAGNOSIS: Because the certainty diagnosis of Alzheimer's disease is defined after autopsy or brain biopsy by the presence of neurofibrillar degeneration (NFD), extracellular senile plaques and vascular deposits of amyloid in the hippocampus amygdalus and the cerebral cortex, some authors have searched for biological ante-mortem markers of AD, particularly in the cerebrospinal fluid (CSF) which is essentially derived from brain tissue. SEARCH FOR MARKERS: Studies have investigated the CSF level of neurotransmitters, neuropeptides, amino acids, trace elements, constituents of NFD and senile plaques in a diagnostic and pathogenic perspective. HOPE FOR DIAGNOSIS: Even though ethical, technical and methodological difficulties met by authors are important and even though many clinical and biological parameters must be taken into account, these studies bring important pathogenic evidence and allow hope that markers of AD which are so necessary for early diagnosis and objective study of therapies will be found.

Alzheimer Disease↗

Abnormal substrate levels that depend upon mitochondrial function in cerebrospinal fluid from Alzheimer patients.

BACKGROUND: Impaired oxidative and energy metabolism are important features in Alzheimer's disease. These metabolic abnormalities may induce functional disturbances and are associated with significant cognitive impairment. OBJECTIVE: To determine whether mitochondrial function is altered by Alzheimer's disease, a quantitative analysis of substrates that enter the tricarboxylic acid cycle was carried out in cerebrospinal fluid (CSF) from Alzheimer patients. METHODS: Organic acid levels related to carbohydrate oxidation were measured in CSF from patients affected by dementia of Alzheimer type (n = 17) and from nondemented elderly controls (n = 17) using a gas chromatography/mass spectrometry system. CSF glucose and glutamine concentrations were determined by a quantitative enzymatic method and by ion exchange chromatography, respectively. RESULTS: Compared to age-matched controls, patients had a higher CSF level of lactate (p = 0.002) and a lower mean level of succinate (p = 0.002), fumarate (p = 0.003) and glutamine (p = 0.0005). The CSF glucose level was not modified. CONCLUSION: Our results suggest an impairment of mitochondrial oxidative metabolism in brain cells of patients with Alzheimer's disease.

Aged↗

Measurement of the amounts of elastic fibers in the skin and temporal arteries of healthy aged individuals by automated image analysis.

BACKGROUND: A quantitative study of dermal and arterial elastic fibers as a function of age was carried out by computerized image analysis. OBJECTIVE: We investigated whether any parallelism can be established between the morphometric parameters of elastic fibers from the skin and the temporal artery in elderly subjects. METHODS: we quantitated the skin elastic fibers of the reticular dermis and the elastic fibers of the temporal artery using a specific staining procedure followed by automated image analysis in 16 subjects of age range 63-87 years. RESULTS: There was a good correlation between the area fraction occupied by the elastic fibers in the unexposed skin (inner part of the upper arm) and aging (r = 0.669, p < 0.01). The area fraction occupied by elastic fibers in unexposed skin was correlated with the area fraction occupied by elastic fibers in the deep part of the temporal artery (r = 0.498, p < 0.05). Actinic elastosis affected both tissues, but there was no correlation between the amount of elastotic material in the exposed skin and the area fraction of elastic fibers in the superficial part of the temporal artery. CONCLUSION: We provided evidence that in sun-protected tissues the area fraction occupied by elastic fibers in dermis and deep part of the temporal artery showed a significant correlation. We proposed that skin biopsies were a valuable diagnostic tool for predicting arterial wall abnormalities of elastic fibers.

Aged↗

[A review of evaluation questionnaires for physical activity].

The need to evaluate or quantify an individual's physical activity often raises the problems of choosing the instrument which most adequately meets the requirements of the study. This article offers a presentation of various questionnaires available in the literature. It proposes a table intended to characterize these questionnaires as well as a summary of validation steps. These tools allow rapid comparisons between questionnaires and are helpful in guiding the user's choice of a well adapted questionnaire.

Exercise↗

Cerebrospinal fluid apolipoprotein E level is increased in late-onset Alzheimer's disease.

Worldwide evidence has recently shown that the allele epsilon4 of apolipoprotein E (ApoE) is a genetic risk factor for Alzheimer's disease (AD) underlining the possible role of apoE in the physiopathology of AD. To evaluate the usefulness of apoE concentration in pathogenesis of AD, we measured the cerebrospinal fluid (CSF) levels of apoE. CSF apoE level was significantly higher in 38 patients with late-onset AD than in 31 control patients and 47 patients suffering from other neurological and related diseases. Higher levels of CSF apoE were also present in a subset of patients with meningoencephalitis, motor neuron disease, and low back pain. The increase of CSF-apoE in AD is in agreement with results from studies that find an increase of mRNA apoE in the brains of AD patients. Compared to other works, these results underline the importance and the difficulties of the selection of the controls. The CSF apoE level seems to be a reflection of neuronal damage and/or an inflammatory reaction that may be common to AD and other neurological and related diseases.

Age of Onset↗

Prospective evaluation of protein bound vitamin B12 (cobalamin) malabsorption in the elderly using trout flesh labelled in vivo with 57Co-cobalamin.

BACKGROUND: The frequency of dietary protein bound vitamin B12 malabsorption in elderly patients remains controversial. AIMS: To evaluate this malabsorption in elderly hospitalised patients using a modified Schilling test. PATIENTS: Fourteen elderly patients with low B12 blood levels were prospectively selected from 394 hospitalised patients. METHODS: The modified Schilling test was performed with trout labelled in vivo. RESULTS: The test was normal in five healthy elderly subjects, in 7/8 patients with pancreatic insufficiency, and in nine non-elderly patients with antral gastritis. The low decision limit was established at 3.3% (median 4.8%). From the 14 elderly patients with low B12 prospectively selected from 394 hospitalised patients, seven had a real deficiency with anaemia and an increased homocysteine and/or methylmalonate serum level. The modified Schilling test showed malabsorption in five of these patients, including two in which the standard Schilling test was normal, and three in which the standard Schilling test was partially corrected by an intrinsic factor. CONCLUSIONS: Protein bound vitamin B12 malabsorption was detected in at least 0.5% of elderly hospitalised patients, using the labelled trout flesh absorption test.

Adult↗

Effects of malnutrition and atherosclerosis on the fatty acid composition of plasma phospholipids in the elderly.

The fatty acid profiles of plasma phospholipids have been compared in 53 elderly subjects suffering from malnutrition (group U, 17 subjects) or from atherosclerosis (group A, 15 subjects). A control group was also included in the study (group C, 21 subjects). Main differences were observed in phosphatidylcholine (PC). In group U, the proportion of monounsaturated fatty acids increased in PC, which was reflected by an increase in unsaturated fatty acids without significant modification of essential fatty acids. In group A, no major modification has been observed statistically, although the proportion of saturated fatty acids tended to increase.

Aged↗

Influence of visual control, conduction, and central integration on static and dynamic balance in healthy older adults.

Aging is associated with decreased balance abilities, resulting in an increased risk of fall. In order to appreciate the visual, somatosensory, and central signals involved in balance control, sophisticated methods of posturography assessment have been developed, using static and dynamic tests, eventually associated with electromyographic measurements. We applied such methods to a population of healthy older adults in order to appreciate the respective importance of each of these sensorial inputs in aging individuals. Posture control parameters were recorded on a force-measuring platform in 41 healthy young (age 28.5 +/- 5.9 years) and 50 older (age 69.8 +/- 5.9 years) adults, using a static test and two dynamic tests performed by all individuals first with eyes open, then with eyes closed. The distance covered by the center of foot pressure, sway area, and anteroposterior oscillations were significantly higher, with eyes open or closed, in older people than in young subjects. Significant differences were noted in dynamic tests with longer latency responses in the group of old people. Dynamic recordings in a sinusoidal test had a more regular pattern when performed eyes open in both groups and evidenced significantly greater instability in old people. These data suggest that vision remains important in maintaining postural control while conduction and central integration become less efficient with age.

Adult↗

[Infectious diarrhea in the aged].

Infectious diarrhoea in the elderly is associated with high morbidity and mortality and need early diagnosis and treatment. Polypathology, malnutrition, polytherapy, length of stay in the hospital and residence in nursing-home contribute to the increasing incidence and gravity of these diseases with aging. Viral gastroenteritis is responsible for epidemic in nursing-home residents. Bacterial gastrointestinal infections are primarily caused by enterotoxigenic agents inducing sporadic or epidemic infections food poisoning. Older adults are more particularly exposed to antibiotic-associated diarrhoea. Clostridium difficle has been increasingly recognized as a cause of pseudomembranous colitis in elderly and is associated with increased mortality. The approach to an old patient with suspected infectious diarrhoea should be to eliminate the likely noninfectious causes, to detect immediate complications due to hydroelectrolytic loss, to initiate early appropriated oral rehydration therapy so as to prevent dehydratation, to avoid the use of antimotility drugs, and to evaluate and to take over nutritional consequences of diarrhoea.

Aged↗

[Monoclonal gammopathy and primary hyperparathyroidism. Apropos of 2 cases and review of the literature].

Frequency of primary hyperparathyroidism (HP) is increased in neoplasia. Though uncommon, both HP and monoclonal gammopathy are not exceptionally associated as seen in a literature review reporting 24 observations. The mechanism of this association remains unclear but does not seems coincidental. Association of hypercalcemia with gammopathy does not suggest systematically malignant hypercalcemia and implies the search for hyperparathyroidism. The authors report two patients presenting respectively a multiple IgD myeloma and an monoclonal gammopathy of undetermined signification associated with a parathyroid adenoma.

Aged↗

Physical deconditioning may be a mechanism for the skeletal muscle energy phosphate metabolism abnormalities in chronic heart failure.

The aim of our study was to investigate the contribution of physical deconditioning in skeletal muscle metabolic abnormalities in patients with chronic heart failure (CHF). Phosphate metabolism was studied in the leg muscle at rest and during exercise by using phosphate 31 nuclear magnetic resonance spectroscopy in a group of 14 patients with New York Heart Association class II and III CHF and left ventricular ejection fraction <40% and in two groups of age-matched healthy volunteers: one group of 7 sedentary and another of 7 trained subjects. Phosphocreatine depletion rate, intracellular pH, and adenosine diphosphate levels in the muscle during exercise were not statistically different in the CHF patients and in the sedentary healthy subjects, but both groups were statistically different from the trained healthy subjects, who had slower phosphocreatine depletion rates, as well as less intracellular acidosis and lower adenosine diphosphate levels during exercise (p = 0.02; analysis of variance). Our results suggest that metabolic changes occurring in the skeletal muscle of patients with CHF may contribute to the limitation of exercise capacity and are most likely to be a consequence of physical deconditioning because they are very similar to what is observed in sedentary and otherwise healthy subjects as compared with trained subjects.

Adult↗

Environmental and genetic factors affecting bone mass. Similarity of bone density among members of healthy families.

OBJECTIVE: To evaluate the relative importance of environmental and genetic factors in the determination of bone mineral density (BMD) and to quantify the risk of low BMD in healthy young adults in relation to the BMD of their parents. METHODS: Dual-energy x-ray absorptiometry study of a series of 129 nuclear families (441 subjects), including 183 children over age 15, was performed. Correlation of BMD in children with BMD in their parents was studied in a linear model, taking into account environmental factors. Logistic regression was used to quantify the relative risk of lower BMD according to the parents' BMD level. RESULTS: BMD was significantly correlated with weight, height, and body mass index (BMI) in all family members, and with parents' alcohol consumption and with physical activity in fathers and sons. The BMD of the children correlated with that of their parents (r = 0.27). The child's BMI, his/her father's BMD and daily calcium intake, and his/her mother's BMD, BMI, and body fat accounted for 41.4% of the variance in the child's BMD. A son had a 3.8 times higher risk of having a low BMD if his father had a low BMD, and a daughter had a 5.1 times higher risk if her mother had a low BMD. CONCLUSION: The BMD of children in healthy families was related to the BMD of their parents as well as to environmental factors, confirming the contribution of genetic inheritance in the determination of bone density in young adults, especially in girls.

Adolescent↗