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P Perrier

Publications and source records attributed to P Perrier.

At least 19 recordsLinked to original sources
PubMed2006

HLA-A*02010102L: a laborious assignment.

In the present report we describe the laborious identification of the A*02010102L allele found in three healthy individuals of a French family who have shown a reduced A2 antigen expression using serological tests since the 1980s. PCR-SSP typing showed a classical A*0201 allele. Sequencing of exons 2, 3 and 4 confirmed this assignment. Sequencing of the whole gene (promoter, introns and exons 1-8) revealed one single point mutation (T to C) at position -101 in the enhancer B element region compared to the A*02010101 allele. This single mutation appears to be related to the reduced expression of the A2 antigen. This allele segregates with the haplotype Cw*12, B44, DR7, DQ2, which is different to the one described earlier.

Alleles↗
PubMed2005

Non-linear elastic properties of the lingual and facial tissues assessed by indentation technique. Application to the biomechanics of speech production.

This paper aims at characterizing the mechanical behavior of two human anatomical structures, namely the tongue and the cheek. For this, an indentation experiment was provided, by measuring the mechanical response of tongue and cheek tissues removed from the fresh cadaver of a 74 year old woman. Non-linear relationships were observed between the force applied to the tissues and the corresponding displacements. To infer the mechanical constitutive laws from these measurements, a finite element (FE) analysis was provided. This analysis aimed at simulating the indentation experiment. An optimization process was used to determine the FE constitutive laws that provided the non-linear force/displacements observed during the indentation experiments. The tongue constitutive law was used for simulations provided by a 3D FE biomechanical model of the human tongue. This dynamical model was designed to study speech production. Given a set of tongue muscular commands, which levels correspond to the force classically measured during speech production, the FE model successfully simulated the main tongue movements observed during speech data.

Aged↗
PubMed2002

New HLA-DRB1*07 allele identified from microlymphocytotoxicity/SSP discrepancies.

A HLA-DRB1*07 variant allele has been identified in a cadaver kidney donor. Serological typing using monoclonal antibodies detected HLA-DR4 and HLA-DR7. HLA class II DNA typing using sequence-specific primer (PCR-SSP) polymerase chain reaction only detected DRB1*04, while sequence-specific oligonucleotide (PCR-SSO) polymerase chain reaction confirmed the presence of both DRB1*04 and DRB1*07 alleles, although two extra reactions were also found. Exon 2 of the HLA-DRB1*07 was isolated using allele-specific PCR, then cloned and sequenced. Four mutations, at positions 170 (T --> C), 171 (C --> T), 174 (C --> G), and 179 (C --> A), were observed. These mutations changed codons 57 and 60 (V --> A; S --> Y, respectively). This amino acid sequence at position 56-61 is only found in DRB1*0811.

Alleles↗
PubMed2001

Variation in anticipatory coarticulation with changes in clarity and rate.

This study tests the hypothesis that the relative timing, or coarticulation, of articulatory movements at VC and CV boundaries is influenced by both the listener's requirement for clarity and the speaker's strategy to economize effort. Movement and acoustic data were collected from 7 subjects who spoke in three conditions: normal, clear, and fast. It was predicted that fast speech would show more coarticulation and clear speech would show less coarticulation than normal speech. The speech materials were designed to investigate coarticulation in the movements of the upper lip and tongue. They consisted of repetitions of [iC(n)u] utterances embedded in carrier phrases, where the number of consonants, n, ranged from 1 to 3. Analyses focused on kinematic measures and the amount of coarticulation (overlap) of the /i-u/ transition movement with the acoustic interval of the /i/. The consonant-string duration was longest in the clear speaking condition and shortest in the fast condition. Compared to the normal condition, peak velocities were higher in the fast and clear speaking conditions, indicating increased effort. The influences of speaking condition on coarticulation and on the formants of the /i/ were small. Thus, even though there was evidence of increased effort in the clear and fast conditions, the hypothesized effects of a trade-off between clarity and economy of effort were minimally evident in formant values for /i/ and measures of coarticulation.

Adult↗
PubMed2001

Regulation of the chemokine system at the level of chemokine receptor expression and signaling activity.

The chemokine system is highly influenced by the microenvironmental context. Regulation of the chemokine system occurs not only at the level of agonist production, but also at the level of chemokine receptor expression. This review provides examples of regulation of the system at the receptor level by modulation of receptor expression in canonical cellular targets (tuning of the system), and induction of novel receptors (shaping of the system), with particular attention to dendritic cells as a cellular model. Receptor signaling activity represents a further potential level of regulation of the system. Finally, chemokines can also influence the microenvironment by modulating gene expression in target cells.

Chemokines↗
PubMed2000

Coupling of a Rydberg electron capture ion source with a quadrupole mass filter.

The coupling of a Rydberg electron capture ion source with a Nermag R10-10H quadrupole mass filter is described. Details are given of the addition to this instrument of a creation cell for atoms excited in Rydberg states. Within the Nermag ion source, such atoms allow attachment of electrons of well-defined thermal energy. SF(6) was used for optimization of the main experimental parameters (gas pressures and voltages applied to the electrodes). The procedure by which Rydberg electron attachment was confirmed is described. A polychlorobiphenyl compound was used to illustrate the performance of this ionization technique. Ion formation was observed in the absence of fragmentation.

Gas Chromatography-Mass Spectrometry↗
PubMed2000

Ultrasonic assessment of variations in thickness of subcutaneous fat during the normal menstrual cycle.

OBJECTIVE: To verify the occurrence of natural variations in thigh and abdominal subcutaneous fat thickness related to the phases of the menstrual cycle, to assess the value of ultrasonography as a reliable method for monitoring subcutaneous fat thickness changes and to evaluate their amplitudes. METHODS: This study included 10 women (19-39 years) who menstruated regularly. None had used oral contraceptives or slimming products during the 3 months prior to the study. At cycle day 2 (CD2), CD6, CD14, CD22, CD27 and CD30 days (CD0: beginning of menstruation), the subjects were submitted to: (1) measurement of weight and thigh perimeters, (2) measurements of thigh and abdomen subcutaneous fatty tissue thickness on B-mode images acquired at 10 MHz. A protocol was designed to guarantee a reproducible repositioning during the whole time course of the study and ultrasound examinations (US) were always performed by the same trained person to avoid inter-examiner variability. RESULTS: Subcutaneous fat thicknesses decreased during the first half of the cycle and reached their lowest values at day 22 (-2.0% for the thighs; -3.3% for the abdominal region). Both thigh and abdomen subcutaneous fat reached their maximum thicknesses during menstruation with respective increases of +2.2 and +4.0%. The observed cyclic amplitude variations in the subcutaneous adipose tissue thickness accounted for 7.3% for the abdominal region and 4.1% for the thighs. CONCLUSION: Variations in adipose tissue thickness during the menstrual cycle could be quantified and monitored by US. The thickness of the thigh and abdominal hypodermis was more important during menstruation and decreased in mid-cycle with a minimum occurring 1 week after ovulation.

Abdominal Muscles↗
PubMed2000

Identification of a new DQB1 allele that appears to have been generated by an interallelic sequence exchange.

The study reports the molecular characterization of a new DQB1 variant initially detected by unusual sequence-specific oligonucleotide (SSO) hybridization patterns in one Caucasoid individual. This new allele is identical to DQB1*0501 except for two silent nucleotide substitutions at codons 49 (GCA-->GCG) and 77 (AGG-->AGA). Compared with DQB1*0502 it differs in three nucleotides at codon 57 changing AGC (encoding Ser) to GTT (encoding Val). Considering the paternal genotype, it appears this new allele might have been generated by an interallelic sequence exchange between the two paternal DQB1 alleles.

Alleles↗
PubMed2000

[Functional evaluation of intraoral reconstructive surgery. A valuable tool: articulatory evaluation of the acoustic signal].

Functional tests are needed to assess the quality of reconstructive surgery after treatment of intraoral cancers. Quality of Life tests are subjective and Cinefluoroscopy is a demanding and non-comparative procedure. We develop here a method to test the capacity of patients to maximize use of their articulatory space. We recorded a corpus of sounds. These sounds were analyzed with classical signal processing procedures. By comparison with a non-distorded sound database, it was possible to evaluate speech disorders, localize the defect, and provide a guide for rehabilitation. This method is an objective, reproductible, and comparative measurement tool.

Cohort Studies↗
PubMed1999

Compensation strategies for the perturbation of French [u] using a lip tube. II. Perceptual analysis.

A perceptual analysis of the French vowel [u] produced by 10 speakers under normal and perturbed conditions (Savariaux et al., 1995) is presented which aims at characterizing in the perceptual domain the task of a speaker for this vowel, and, then, at understanding the strategies developed by the speakers to deal with the lip perturbation. Identification and rating tests showed that the French [u] is perceptually fairly well described in the [F1, (F2-F0)] plane, and that the parameter (((F2-F0) + F1)/2) (all frequencies in bark) provides a good overall correlate of the "grave" feature classically used to describe the vowel [u] in all languages. This permitted reanalysis of the behavior of the speakers during the perturbation experiment. Three of them succeed in producing a good [u] in spite of the lip tube, thanks to a combination of limited changes on F1 and (F2-F0), but without producing the strong backward movement of the tongue, which would be necessary to keep the [F1,F2] pattern close to the one measured in normal speech. The only speaker who strongly moved his tongue back and maintained F1 and F2 at low values did not produce a perceptually well-rated [u], but additional tests demonstrate that this gesture allowed him to preserve the most important phonetic features of the French [u], which is primarily a back and rounded vowel. It is concluded that speech production is clearly guided by perceptual requirements, and that the speakers have a good representation of them, even if they are not all able to meet them in perturbed conditions.

Adult↗
PubMed1999

[Association of sarcoidosis and hemorrhagic rectocolitis in an insulin-dependent diabetic].

Ulcerative colitis and sarcoidosis are seldom associated. A 33-year-old diabetic man developed simultaneously a rectitis and a non-productive cough leading to the diagnosis of ulcerative colitis and sarcoidosis. These diagnoses are discussed because of the possible gastrointestinal lesions from sarcoidosis or the respiratory disorders due to ulcerative colitis. Some pathophysiological evidence can be found in this case in favor of a non-fortuitous association.

Adult↗
PubMed1996

The equilibrium point hypothesis and its application to speech motor control.

In this paper, we address a number of issues in speech research in the context of the equilibrium point hypothesis of motor control. The hypothesis suggests that movements arise from shifts in the equilibrium position of the limb or the speech articulator. The equilibrium is a consequence of the interaction of central neural commands, reflex mechanisms, muscle properties, and external loads, but it is under the control of central neural commands. These commands act to shift the equilibrium via centrally specified signals acting at the level of the motoneurone (MN) pool. In the context of a model of sagittal plane jaw and hyoid motion based on the lambda version of the equilibrium point hypothesis, we consider the implications of this hypothesis for the notion of articulatory targets. We suggest that simple linear control signals may underlie smooth articulatory trajectories. We explore as well the phenomenon of intraarticulator coarticulation in jaw movement. We suggest that even when no account is taken of upcoming context, that apparent anticipatory changes in movement amplitude and duration may arise due to dynamics. We also present a number of simulations that show in different ways how variability in measured kinematics can arise in spite of constant magnitude speech control signals.

Biomechanical Phenomena↗
PubMed1993

A novel HLA haplotype containing a DRB5 gene associated with the DRB1*0103 allele.

A new hybrid haplotype, a DRB1*0103 allele associated with a DRB5*0101 allele, was found in a French Caucasoid family and has been described here. When these cells were typed by serology, contrarily to cells with the DR1 + 2s haplotype, they did not seem to be triplets. The reactivity of these cells with the DR2 allosera led to a false serological HLA-DR typing. RFLP analysis and DNA oligotyping after DR1-DRB1, DR2-DRB1 and DRB5 group-specific amplifications showed that there was no DR2-DRB1 product in these cells and demonstrated the segregation of a DR103 DR51 haplotype in the family.

Alleles↗
PubMed1993

[Population genetics, immunologic evaluation and Buerger's disease. Projection through a personal study comprising 127 cases of juvenile arteriopathy].

The analysis of anamnestic, clinical and arteriographic parameters in 127 young patients with arterial disease of the lower limbs allowed a definite distinction between thromboangiitis obliterans (TAO) and early-onset atheroma, even if the etiopathogenic of TAO is still obscure. The HLA gene frequency has been determined in 54 patients (14 TAO, 40 early atheroma) and has been compared with local blood donors and with caucased subjects from the IXth Workshop. The results (higher frequency of HLA A28, AX, B53 and BX in the TAO group) have, however, a dubious significance. Furthermore, there were no differences between TAO and early atheroma in a comparative study of immunological parameters (anti-nuclear antibodies, circulating immune complexes, C3, C4 and CH50, cryoglobulin) in 72 patients (22 TAO, 50 early atheroma). So, neither a genetic predisposition nor a dysimmunity could be involved in the pathogenesis of TAO.

Adult↗
PubMed1992

Vocal tract area function estimation from midsagittal dimensions with CT scans and a vocal tract cast: modeling the transition with two sets of coefficients.

The generation of area functions from measurements of the sagittal section is an important step in the study of the relation between vocal tract geometry and speech acoustics. We present a new model to perform this transformation, inspired by the alpha beta model of Heinz & Stevens (1965). Our model is based on analysis of a vocal tract cast for large sagittal dimensions and for small sagittal dimensions on CT scans of the vocal tract constriction zones for the three cardinal vowels [i, a, u] of French. We extracted two sets of coefficients, appropriate for large and small sagittal dimensions respectively. We then compared the predictions of the model with those of other models from the literature. Finally, the usefulness of this dual coefficient procedure for the acoustic simulation of vowels was tested using sagittal sections generated by an acoustic model of the vocal tract.

Female↗