Philippe JEAN-PIERRE

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/10/1998
• Auteurs : Djamel KhadraouiChristophe DebainPhilippe MartinetPierre BontonJean Gallice
• Organismes : Laboratoire des sciences et matériaux pour l'électronique et d'automatique Technologies et systèmes d'information pour les agrosystèmes Centre national du machinisme agricole, du génie rural, des eaux et forêts Laboratoire des sciences et matériaux pour l'électronique et d'automatique Laboratoire des sciences et matériaux pour l'électronique et d'automatique Systèmes Microélectroniques et Traitement d'Images Laboratoire des sciences et matériaux pour l'électronique et d'automatique
• Publié dans The International Journal of Robotics Research le 01/11/2020

---

Résumé : This article presents a real-time control system for an agricultural mobile machine (vehicle) based on an on-board vision system using a single camera. This system has been designed in order to help human beings in repetitive and di cult tasks in the agricultural domain. The aim of the robotics application concerns the control of the vehicle with regard to the reap limit detected in image space. The perception aspect in relation with the application has been described in previous work, and here we deal with the control aspect. We integrate image features issued from the modelling of the scene in the control loop, in order to perform image-based servoing technique. The vehicle behaviour described here concerns bicycle and neural models, and three control laws are then synthesized. The rst and the second are modelling approaches and use an interaction between the scene and the image space. They are based on regulation of a task function. The third is a \black-box modelling" technique and is based on a neural network. Finally, experimental results obtained with these di erent control laws in different conditions are presented and discussed.

---

Fichiers liés : ijrr97.pdf

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/09/1998
• Auteurs : Philippe LahayeKhalid TaziJean-Pierre RonaOlivier DellisDidier LebrecRichard Moreau
• Organismes : Université Denis Diderot Ampère, Département Méthodes pour l'Ingénierie des Systèmes Ampère, Département Automatique pour l'Ingénierie des Systèmes
• Publié dans Hepatology le 30/10/2020

---

Résumé : Protein kinase C (PKC) modulates the activity and phosphorylation of the catalytic α-subunit of sodium-potassium-adenosine triphosphatase (Na + /K + ATPase) in normal arteries. Because PKC is altered in cirrhotic aortae, Na + /K + ATPase may also be altered in these arteries. The aim of the present study was to investigate α-subunit activity and phosphorylation in aortae from normal and cirrhotic rats, under baseline conditions and during exposure to PKC modulators. α-Subunit activity was assessed by measuring the amount of 32 P released by hydrolysis of [γ- 32 P]ATP in freshly isolated cell membranes (in the absence of PKC modulators only) and membrane depolarization caused by ouabain-induced α-subunit inhibition in isolated aortae (in the absence and presence of PKC modulators). α-Subunit phosphorylation was assessed by incorporation of 32 P into α-subunits. Staurosporine, a PKC inhibitor, and phorbol 12,13-dibutyrate (PDBU), a PKC activator, were used. In addition, α-subunit expression was studied by Western blot analysis. In the absence of PKC modulators, the amount of 32 P released by hydrolysis of [γ- 32 P]ATP and ouabain-induced membrane depolarization were significantly lower in cirrhotic than in normal aortae. Staurosporine suppressed ouabain-induced membrane depolarization in cirrhotic and normal arteries. Ouabain-induced membrane depolarization was similar in cirrhotic aortae exposed to PDBU and in normal arteries studied under baseline conditions. α-Subunit phosphorylation was significantly lower in cirrhotic than in normal aortae, in aortae under baseline conditions, and in arteries exposed to staurosporine. Phosphorylation of the α-subunit was similar in cirrhotic aortae exposed to PDBU and in normal arteries under baseline conditions. Western blot analysis showed that the amount of α-subunit did not significantly differ between cirrhotic and normal aortae. In conclusion, a decrease in baseline Na + /K + ATPase α-subunit activity occurs in aortae from cirrhotic rats as a result of reduced basal PKC activity. This PKC-dependent decreased α-subunit activity may be caused by a reduction in PKC-induced α-subunit phosphorylation.

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/09/1998
• Auteurs : Olivier ValdenaireMarion Maus-MoattiJean-Didier VincentJacques MalletPhilippe Vernier
• Organismes : F. Hoffmann-La Roche [Basel] Laboratoire de Génétique Moléculaire de la Neurotransmission et des Processus Neurodégénératifs [APHP Pitié-Salpêtrière] Collège de France - Chaire Neuropharmacologie Institut de Neurobiologie Alfred Fessard Laboratoire de Génétique Moléculaire de la Neurotransmission et des Processus Neurodégénératifs [APHP Pitié-Salpêtrière] Institut de Neurobiologie Alfred Fessard
• Publié dans Journal of Neurochemistry le 25/10/2020

---

Résumé : The time course of D2 receptor expression assessed by the levels of the corresponding binding sites and mRNA was studied in rat striatum during ontogenesis and in primary cultures of cells taken at embryonic day (E) 17 and postnatal day (P) 4. In the two experimental situations, the amount of D2 receptor mRNA and number of binding sites increased regularly from E16 to P15, indicating that expression of D2 receptors in striatal neurons occurs independently from a dopaminergic input. Incubation of striatal primary cultures with 10(-5) M retinoic acid significantly increased the level of D2 receptor mRNA, whereas thyroid hormone, vitamin D3, and steroid hormones (estradiol, testosterone, and corticosterone) had no effect. The transcriptional activity of the rat D2 receptor gene promoter region, which bears a retinoic acid-responsive element, was increased by retinoic acid in transfected C6 glioma cells but not in transfected MMQ prolactin cells. Thyroid hormone and vitamin D3 were not effective in either cell line. Finally, mutations of the putative retinoic acid-responsive element inhibited the transcriptional effect of retinoic acid. These results suggest that retinoic acid is a key factor in regulation of the embryonic onset of the dopaminergic D2 receptor.

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/08/1998
• Auteurs : Thierry BienvenuVincent Des PortesAnne de Saint-MartinNathalie McdonellPierre BilluartAlain CarriéMarie-Claude VinetPhilippe CouvertDaniela TonioloHans-Hilger RopersClaude MoraineHans van BokhovenJean-Pierre FrynsAxel KahnCherif BeldjordJamel Chelly
• Organismes : Institut de génétique et biologie moléculaire et cellulaire Institut de Génétique et de Biologie Moléculaire et Cellulaire Institut de génétique et biologie moléculaire et cellulaire Institut de Génétique et de Biologie Moléculaire et Cellulaire
• Publié dans Human Molecular Genetics le 26/10/2020

---

Résumé : Non-specific X-linked mental retardation (MRX) is a very common disorder which affects approximately 1 in 600 males. Despite this high frequency, little is known about the molecular defects underlying this disorder, mainly because of the clinical and genetic heterogeneity which is evident from linkage studies. Recently, a collaborative study using the candidate gene approach demonstrated the presence of mutations in GDIalpha, a Rab GDP-dissociation inhibitor encoded by a gene localized in Xq28, associated with non-specific mental retardation. GDIalpha is mainly a brain-specific protein that plays a critical role in the recycling of Rab GTPases involved in membrane vesicular transport. The study presented here was designed to assess the prevalence of mutations in the GDIalpha in mentally retarded patients and to discuss the clinical phenotypes observed in affected individuals. Mutation screening of the whole coding region of the GDIalpha gene, using a combination of denaturing gradient gel electrophoresis and direct sequencing, was carried out in 164 patients found negative for expansions across the FRAXA GCC repeat. In addition to the nonsense mutation recently reported in MRX48, we have identified a novel missense mutation in exon 11 of the GDIalpha gene in one familial form of non-specific mental retardation. In this family (family R), all affected males show moderate to severe mental retardation, and the X-linked semidominant inheritance is strongly suggested by the severe phenotypes in males with respect to mildly affected females or unaffected obligatory carriers. This study showed that the prevalence of GDIalpha mutations in non-specific mental retardation could be estimated to be 0.5-1%, and molecular diagnosis and genetic counselling in some cases of non-specific mental handicap can now be provided.

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/08/1998
• Auteurs : Sandrine BlanchetBertrand FavierGeneviève ChevalierJean-Jacques MichaillePhilippe KastnerPierre Chambon
• Organismes : Institut de Génétique et de Biologie Moléculaire et Cellulaire Institut de génétique et biologie moléculaire et cellulaire Institut de génétique et biologie moléculaire et cellulaire Institut de Génétique et de Biologie Moléculaire et Cellulaire
• Publié dans Journal of Investigative Dermatology le 24/10/2020

---

Résumé : Embryonic mouse upper-lip skin explants treated with 16.7 microM all-trans retinoic acid (tRA) give rise to a glandular metaplasia of hair vibrissa follicles; however, at this concentration, tRA can activate not only the three retinoic acid receptors (RARalpha, beta, and gamma), but also the retinoid X receptors (RXRalpha, beta, and gamma) as a consequence of its isomerization to 9-cis retinoic acid. We therefore studied the respective roles of the RXR and RAR by treating RARalpha(-/-), beta(-/-), and gamma(-/-) skin explants with tRA and wild-type explants with synthetic retinoids specific for RXR or for each of the RAR. The null mutation of the RARalpha, RARbeta, and RARgamma genes did not prevent tRA-induced hair glandular metaplasia, but RARgamma inactivation dramatically reduced its ratio. As demonstrated by treating explants with a RAR- or a RXR-specific panagonist (CD367 and Ro25-7386, respectively), RAR are primarily responsible for this metaplasia. The use of two retinoids (Ro40-6055, 8 x 10(-3) microM, or CD437, 7.7 x 10(-2) microM) that are believed to act, respectively, as a RARalpha- or a RARgamma-specific agonist showed that both these receptors can initiate a metaplasia. In contrast, BMS453, a RARbeta-specific agonist, was unable to give rise to any metaplasia. Nevertheless, the highest degrees and ratios of metaplasia were only obtained after treatment with the CD367 RAR panagonist, or with either Ro40-6055 or CD437 at a concentration sufficient to allow the activation of the three RAR, suggesting that RARbeta activation is required for a metaplasia of all vibrissae.

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/08/1998
• Auteurs : Sylviane BoularandNicole Faucon BiguetBernadette VidalMichèle VeronJacques MalletJean-Didier VincentSylvie DufourPhilippe Vernier
• Organismes : Laboratoire de Génétique Moléculaire de la Neurotransmission et des Processus Neurodégénératifs [APHP Pitié-Salpêtrière] Laboratoire de Génétique Moléculaire de la Neurotransmission et des Processus Neurodégénératifs [APHP Pitié-Salpêtrière] Laboratoire de Physiologie Générale et Comparée Institut de Neurobiologie Alfred Fessard Laboratoire de Génétique Moléculaire de la Neurotransmission et des Processus Neurodégénératifs [APHP Pitié-Salpêtrière] Institut de Neurobiologie Alfred Fessard Laboratoire de Physiologie Générale et Comparée Institut de Neurobiologie Alfred Fessard
• Publié dans Journal of Neurochemistry le 25/10/2020

---

Résumé : We report the isolation of a full-length eel tyrosine hydroxylase (TH) cDNA that is characterized by a long 3' untranslated region and by a diversity restricted to the 3' end owing to the differential use of three polyadenylation signals. The longest eel TH mRNA was distinctive in the presence of four pentameric elements (AUUUA) in the AU-rich 3' noncoding region. Such a diversity could provide the basis of posttranscriptional or translational regulation of eel TH gene expression. Comparison of the eel TH sequence with those of other aromatic amino acid hydroxylases (TH, tryptophan hydroxylase, and phenylalanine hydroxylase) and phylogenetic analysis confirmed that the N-terminal regulatory domain is highly divergent, contrasting with the conservation of the catalytic core of the enzyme. Molecular phylogenies including the available sequences of the three hydroxylase genes suggested that the duplication of their common ancestor occurred before the emergence of arthropods. The regional expression of the eel TH mRNA was studied by semiquantitative PCR, northern blots, and in situ hybridization and compared with the immunocytochemical localization of TH protein. The data showed that TH mRNA is mostly expressed in the olfactory and hypothalamic areas, whereas sparse TH-expressing cell bodies are present in the telencephalic region and brainstem. No labeling was detected in the mesencephalic area, in striking contrast with that found in amphibians and amniotes.

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/08/1998
• Auteurs : Chantal AndriéPhilippe Jean-BaptisteCatherine PierrePascale DéjardinRenaud FichezJean-Jacques PoupeauFrancis Rougerie
• Organismes : Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] Glaces et Continents, Climats et Isotopes Stables Centre ORSTOM Nouméa Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] Centre Scientifique de Monaco
• Publié dans Geochimica et Cosmochimica Acta le 25/10/2020

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/08/1998
• Auteurs : Laurent FauchierDominique BabutyMarie Laurence AutretPhilippe PoretPierre CosnayJean Paul Fauchier
• Organismes : CHU Trousseau [Tours] Centre Hospitalier Régional Universitaire de Tours Centre Hospitalier Régional Universitaire de Tours
• Publié dans Journal of the Autonomic Nervous System le 26/10/2020

---

Résumé : Frequency-domain analysis of heart rate variability provides information about influences of autonomic nervous system on the heart and can be measured on short-term or long-term electrocardiogram recording. We compared heart rate variability on 24 h electrocardiogram recording with measurements of heart rate variability over shorter periods of 1 h and 12 h in order to determine the influence of duration and hour of recording on the heart rate variability parameters in the frequency domain. Heart rate variability was analyzed in 24 subjects with normal heart, with measurement of total power (Tot P), ULF, VLF, LF, HF and LF/HF ratio. Reference measurements over 24 h were compared with measurements over 4 periods of 1 h (2 AM-3 AM, 8 AM-9 AM, 2 PM-3 PM, 8 PM-9 PM) and over 4 periods of 12 h (2 AM-2 PM, 8 AM-8 PM, 2 PM-2 AM, 8 PM-8 AM). The correlations with measurements over 24 h were lower for the measurements over 1 h than for the measurements over 12 h. ULF had the lowest mean of correlation coefficients for measurements over 1 h and 12 h, whereas the other frequency bands had high correlations with measurements over 24 h. When using Bland and Altman method, only measurements over 2 AM-2 PM and 2 PM-2 AM periods were a reliable estimation of heart rate variability over 24 h.

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/07/1998
• Auteurs : Jean Luc CharlouYves FouquetHenri BougaultJean DonvalJoel EtoubleauPhilippe Jean-BaptisteArnaud DapoignyPierre AppriouPeter Rona
• Organismes : Institut Français de Recherche pour l'Exploitation de la Mer Institut Français de Recherche pour l'Exploitation de la Mer Institut Français de Recherche pour l'Exploitation de la Mer Institut Français de Recherche pour l'Exploitation de la Mer Institut Français de Recherche pour l'Exploitation de la Mer Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] Glaces et Continents, Climats et Isotopes Stables Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] Glaces et Continents, Climats et Isotopes Stables Université de Brest Rutgers, The State University of New Jersey [New Brunswick]
• Publié dans Geochimica et Cosmochimica Acta le 25/10/2020

---

Source

---

• Type de publi. : Article dans une revue
• Date de publi. : 01/07/1998
• Auteurs : Philippe FossierMarie-Françoise DieblerJean-Pierre MothetMaurice IsraëlLadislav TaucGérard Baux
• Organismes : Laboratoire de neurobiologie cellulaire et moléculaire Institut de Neurobiologie Alfred Fessard Laboratoire de neurobiologie cellulaire et moléculaire Institut de Neurobiologie Alfred Fessard Laboratoire de neurobiologie cellulaire et moléculaire Institut de Neurobiologie Alfred Fessard Laboratoire de neurobiologie cellulaire et moléculaire Institut de Neurobiologie Alfred Fessard Laboratoire de neurobiologie cellulaire et moléculaire Institut de Neurobiologie Alfred Fessard Laboratoire de neurobiologie cellulaire et moléculaire Institut de Neurobiologie Alfred Fessard
• Publié dans Neuroscience le 24/10/2020

---

Résumé : 2,5-Diterbutyl-1,4-benzohydroquinone, a specific blocker of Ca2+-ATPase pumps, increased acetylcholine release from an identified synapse of Aplysia, as well as from Torpedo and mouse caudate nucleus synaptosomes. Because 2,5-diterbutyl-1,4-benzohydroquinone does not change the presynaptic Ca2+ influx, the enhancement of acetylcholine release could be due to an accumulation of Ca2+ in the terminal. This possibility was further checked by studying the effects of 2,5-diterbutyl-1,4-benzohydroquinone on twin pulse facilitation, classically attributed to residual Ca2+. While preventing the fast sequestration of Ca2+ by presynaptic organelles, 2,5-diterbutyl-1,4-benzohydroquinone magnified both twin pulse facilitation observed under low extracellular Ca2+ concentration and twin pulse dysfacilitation observed under high extracellular Ca2+ concentration. Thus, it is concluded that 2,5-diterbutyl-1,4-benzohydroquinone, by preventing Ca2+ buffering near transmitter release sites, modulates acetylcholine release. As 2,5-diterbutyl-1,4-benzohydroquinone was also shown to decrease by 50% the uptake of 45Ca2+ by isolated synaptic vesicles, we propose that synaptic vesicles can control the presynaptic Ca2+ concentration triggering the release of neurotransmitter.

---

Source