Publications by authors named "Nicolas A"

Patients with restless leg syndrome (RLS) complain of motor restlessness, usually occurring while they rest in the evening. Two immobilization tests have been described to assess leg restlessness in these patients. In the first test, the patient sits in bed with his or her legs outstretched while electromyograms are recorded from right and left anterior tibialis muscles for an hour (Suggested Immobilization Test [SIT]); in the second test, the legs are immobilized in a stretcher (Forced Immobilization Test [FIT]).

View Article and Find Full Text PDF

First- and second-night effects on the electroencephalogram (EEG) were investigated by means of polygraphic sleep recordings and all-night spectral analysis. Eighteen normal subjects were studied for three consecutive nights in a hospital sleep laboratory. Visual sleep scoring showed that there was a first-night effect in normal subjects similar to that reported previously [increased wakefulness; decreased total sleep time, sleep efficiency, and rapid eye movement (REM) sleep].

View Article and Find Full Text PDF

New discoveries in perceptual psychology, brain chemistry, brain evolution, brain development, ethology, cultural anthropology, the more recent work of MacLean on the structure of the brains and the discovery by Gazzaniga of the role of the, so-called, "interpreter module," are the foundations of a new paradigm on human cortical information processing, called by its discoverer, Dr. M. Colavito, the "biocultural paradigm.

View Article and Find Full Text PDF

The role of PRL in human breast tumorigenesis is not well understood. One of the limitations is the difficulty of accurately measuring PRL receptors (PRLR) in human tissues. We established a quantitative PCR method (Q-PCR) in T-47D human breast cancer cells and applied it to 29 patients, 25 of whom presented with either cancer or fibroadenoma.

View Article and Find Full Text PDF

To assess the topographical distribution of sleep spindles and K-complexes, four 15-minute samples of stage 2 sleep in a group of eight healthy young adults were analyzed. Results show that a majority of spindles generated are detected over central regions, and that K-complexes are markedly predominant over prefrontal and frontal regions. These findings are consistent with the single-spindle generator hypothesis and raise questions concerning the Rechtschaffen and Kales rules for scoring K-complexes.

View Article and Find Full Text PDF

In the yeast Saccharomyces cerevisiae, meiotic recombination is initiated by DNA double-stranded breaks (DSBs) occurring in micrococcal nuclease (MNase)-hypersensitive regions of the chromatin. MNase-sensitive sites also undergo meiosis-specific alterations in chromatin structure prior to the appearance of DSBs. DSB formation requires the products of numerous genes.

View Article and Find Full Text PDF

We have isolated a cDNA clone encoding the human ribosomal protein L38 (HSRPL38). The longest ORF of the cDNA predicts a lysine-rich small polypeptide identical to the rat RPL38 protein (100% identity), and sharing a 84% of identity to the tomato RPL38 protein sequence. Northern blot analysis of a number of epithelial cell lines showed that the HSRPL38 is encoded by a mRNA ubiquitously expressed.

View Article and Find Full Text PDF

A selective and sensitive high-performance liquid chromatographic (HPLC) method has been developed for the measurement of colistin residues in milk and in four bovine tissues (i.e., muscle, liver, kidney, and fat).

View Article and Find Full Text PDF

From July 1989 to July 1994, a total of 44 popliteal-to-distal artery bypasses were performed in 36 patients (29 men and seven women, mean age 62 +/- 10 years). These procedures accounted for 8.8% of all infrainguinal revascularizations performed during that period.

View Article and Find Full Text PDF

X-ray data have been recorded to 1.0 A resolution from a crystal of Fusarium solani cutinase using synchrotron radiation and an imaging-plate scanner. The anisotropic treatment of thermal motion led to a fivefold increase in accuracy and to a considerable quality improvement in the electron density maps with respect to an intermediate isotropic model.

View Article and Find Full Text PDF

In the yeast Saccharomyces cerevisiae, meiotic recombination is initiated by transient DNA double-strand breaks (DSBs) that are repaired by interaction of the broken chromosome with its homologue. To identify a large number of DSB sites and gain insight into the control of DSB formation at both the local and the whole chromosomal levels, we have determined at high resolution the distribution of meiotic DSBs along the 340 kb of chromosome III. We have found 76 DSB regions, mostly located in intergenic promoter-containing intervals.

View Article and Find Full Text PDF

Type II topoisomerases help regulate DNA topology during transcription, replication and recombination by catalysing DNA strand transfer through transient double-stranded breaks. All type II topoisomerases described so far are members of a single protein family. We have cloned and sequenced the genes encoding the A and B subunits of topoisomerase II from the archaeon Sulfolobus shibatae.

View Article and Find Full Text PDF

Epidemiological studies of aging are usually confronted with the presence of numerous pathologies or environmental factors which make it difficult to identify the effects of aging individually. One way of reducing the variability among individuals is to use well defined criteria to select the study population. This is the choice that was made for the New Mexico and Toulouse Aging Process Studies, which were particularly turned towards successful aging.

View Article and Find Full Text PDF

The purpose of this study was to compare the patient tolerance and efficacy, as magnetic resonance imaging negative oral contrast agents, of a mixture of clay compound bentonite and low density barium sulfate suspension with that of higher density barium sulfate. Twenty patients were randomized into two groups: 10 patients receiving a mixture of low concentration 60% w/v barium sulfate plus 2.5% w/v bentonite, and 10 patients receiving 220% w/v barium sulfate Liuqid-HD (E-Z-EM, Westbury, NY).

View Article and Find Full Text PDF

Determination of the protein profile of orientation (PPO) is now considered by some authors as a means of improving the diagnosis in internal medicine. The feasibility of systematizing this practice was investigated in 76 outpatients (79 included, three excluded secondarily) seen for pathology of undetermined diagnosis. The 79 patients (mean age: 52 years) underwent the classical biological explorations plus PPO.

View Article and Find Full Text PDF

In characterizing mutants and covalently inhibited complexes of Fusarium solani cutinase, which is a 197-residue lipolytic enzyme, 34 variant structures, crystallizing in 8 different crystal forms, have been determined, mostly at high resolution. Taking advantage of this considerable body of information, a structural comparative analysis was carried out to investigate the dynamics of cutinase. Surface loops were identified as the major flexible protein regions, particularly those forming the active-site groove, whereas the elements constituting the protein scaffold were found to retain the same conformation in all the cutinase variants studied.

View Article and Find Full Text PDF

By using slow thermal transients of reduced amplitude (+/- 3 degrees C (thermoneutrality in humans sleeping nude) during only 1 night (experimental, EX), we have advanced the minimum of rectal temperature (Tre) and the peak of their paradoxical sleep propensity (PPSP) of sleeping subjects. During this EX night Tre minimum was significantly (P = 0.0001) advanced by 143 min versus that observed during baseline night spent at thermoneutrality.

View Article and Find Full Text PDF

The last five years have witnessed the solution of a large number of lipase structures, which has led, among other insights, to the structural interpretation of the interfacial activation phenomenon in terms of 'lid' opening. This interpretation has been extended this year to include phospholipase A2. Recent structural studies on lipases have provided data on the detailed mechanisms underlying the behaviour of lipases: how they bind to inhibitors or substrates, and what interactions occur between their hydrophobic face and hydrophobic molecules, for example.

View Article and Find Full Text PDF

Background: Meiotic recombination between homologous chromosomes in the yeast Saccharomyces cerevisiae is initiated by the formation of DNA double-strand breaks (DSBs). The mechanism of DSB formation and the factors that determine their frequency and location have yet to be elucidated. Current studies of meiotic recombination are also concerned with the question of the functional relationship between DSB formation and the other meiotic processes of homology searching, pairing and synapsis of homologues.

View Article and Find Full Text PDF

The aim of this study was to determine the sensitivity of different methods--two commercial polymerase chain reaction (PCR) kits (a protocol of nested PCR and a protocol of amplification of the IS6110 insertion element), the radiometric Bactec system, the Septi-Chek AFB culture system, and culture in Löwenstein-Jensen (LJ) solid medium--for the detection of Mycobacterium tuberculosis. One hundred clinical samples from 51 patients with culture-positive tuberculosis (81 specimens) and 19 controls (19 specimens) were used. Eighty-nine percent of the samples were smear negative.

View Article and Find Full Text PDF

Site-specific endonucleases have been found in various eukaryotic organelles such as mitochondria, chloroplasts and nuclei. These endonucleases initiate site-specific or homologous gene conversion in mitochondrial and nuclear DNA. Here, we report a new site-specific endonuclease activity, Endo.

View Article and Find Full Text PDF

Objective: We performed this study to evaluate the incidence and significance of ring enhancement after i.v. administration of an ultrasmall superparamagnetic iron oxide (USPIO) particle (Code 7227), a reticuloendothelial contrast agent with potential use as a blood-pool agent, for characterizing focal hepatic lesions.

View Article and Find Full Text PDF