1
|
Faure F, Baranger J, Alison M, Boutillier B, Frérot A, Lim C, Planchette G, Prigent M, Tanter M, Baud O, Biran V, Demené C. Quantification of brain-wide vascular resistivity via ultrafast Doppler in human neonates helps early detection of white matter injury. J Cereb Blood Flow Metab 2024:271678X241232197. [PMID: 38340789 DOI: 10.1177/0271678x241232197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
Preterm birth is associated with cerebrovascular development disruption and can induce white matter injuries (WMI). Transfontanellar ultrasound Doppler is the most widely used clinical imaging technique to monitor neonatal cerebral vascularisation and haemodynamics based on vascular indexes such as the resistivity index (RI); however, it has poor predictive value for brain damage. Indeed, these RI measurements are currently limited to large vessels, leading to a very limited probing of the brain's vascularisation, which may hinder prognosis. Here we show that ultrafast Doppler imaging (UfD) enables simultaneous quantification, in the whole field of view, of the local RI and vessel diameter, even in small vessels. Combining both pieces of information, we defined two new comprehensive resistivity parameters of the vascular trees. First, we showed that our technique is more sensitive in the early characterisation of the RI modifications between term and preterm neonates and for the first time we could show that the RI depends both on the vessel diameter and vascular territory. We then showed that our parameters can be used for early prediction of WMI. Our results demonstrate the potential of UfD to provide new biomarkers and pave the way for continuous monitoring of neonatal brain resistivity.
Collapse
Affiliation(s)
- Flora Faure
- Physics for Medicine, INSERM U1273, CNRS, ESPCI, PSL Research University, Paris, France
| | - Jérôme Baranger
- Physics for Medicine, INSERM U1273, CNRS, ESPCI, PSL Research University, Paris, France
| | - Marianne Alison
- Department of Radiology, Assistance Publique-Hôpitaux de Paris, Robert Debré Children's Hospital, University Paris Cité, Paris, France
| | - Béatrice Boutillier
- Neonatal Intensive Care Unit, Assistance Publique-Hôpitaux de Paris, Robert Debré Children's Hospital, University Paris Cité, Paris, France
| | - Alice Frérot
- Neonatal Intensive Care Unit, Assistance Publique-Hôpitaux de Paris, Robert Debré Children's Hospital, University Paris Cité, Paris, France
| | - Chung Lim
- Department of Radiology, Assistance Publique-Hôpitaux de Paris, Robert Debré Children's Hospital, University Paris Cité, Paris, France
| | - Grégory Planchette
- Department of Radiology, Assistance Publique-Hôpitaux de Paris, Robert Debré Children's Hospital, University Paris Cité, Paris, France
| | - Mickael Prigent
- Department of Radiology, Assistance Publique-Hôpitaux de Paris, Robert Debré Children's Hospital, University Paris Cité, Paris, France
| | - Mickaël Tanter
- Physics for Medicine, INSERM U1273, CNRS, ESPCI, PSL Research University, Paris, France
| | - Olivier Baud
- Department of Pediatric, University Hospital of Geneva, University of Geneva, Geneva, Switzerland. O.B. is also with INSERM U1141, Robert Debré Children's Hospital, University Paris Cité, Paris, France
| | - Valérie Biran
- Neonatal Intensive Care Unit, Assistance Publique-Hôpitaux de Paris, Robert Debré Children's Hospital, University Paris Cité, Paris, France
- I2D2, INSERM U1141, University Paris Cité Paris, France
| | - Charlie Demené
- Physics for Medicine, INSERM U1273, CNRS, ESPCI, PSL Research University, Paris, France
| |
Collapse
|
2
|
Albert B, Raquin C, Prigent M, Nadot S, Brisset F, Yang M, Ressayre A. Successive microsporogenesis affects pollen aperture pattern in the tam mutant of Arabidopsis thaliana. Ann Bot 2011; 107:1421-1426. [PMID: 21489970 PMCID: PMC3101141 DOI: 10.1093/aob/mcr074] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 02/01/2011] [Accepted: 02/14/2011] [Indexed: 05/29/2023]
Abstract
BACKGROUND AND AIMS The tam (tardy asynchronous meiosis) mutant of Arabidopsis thaliana, which exhibits a modified cytokinesis with a switch from simultaneous to successive cytokinesis, was used to perform a direct test of the implication of cytokinesis in aperture-pattern ontogeny of angiosperm pollen grains. The aperture pattern corresponds to the number and arrangement of apertures (areas of the pollen wall permitting pollen tube germination) on the surface of the pollen grain. METHODS A comparative analysis of meiosis and aperture distribution was performed in two mutant strains of arabidopsis: quartet and quartet-tam. KEY RESULTS While the number of apertures is not affected in the quartet-tam mutant, the arrangement of the three apertures is modified compared with the quartet, resulting in a different aperture pattern. CONCLUSIONS These results directly demonstrate the relationship between the type of sporocytic cytokinesis and pollen aperture-pattern ontogeny.
Collapse
Affiliation(s)
- B Albert
- Laboratoire Ecologie Systématique et Evolution, Univ. Paris-Sud, Orsay, France.
| | | | | | | | | | | | | |
Collapse
|
3
|
Prigent M, Teissier N, Peuchmaur M, El Maleh-Berges M, Philippe-Chomette P, Cardin P, Orbach D. Sialoblastoma of salivary glands in children: chemotherapy should be discussed as an alternative to mutilating surgery. Int J Pediatr Otorhinolaryngol 2010; 74:942-5. [PMID: 20554035 DOI: 10.1016/j.ijporl.2010.01.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Revised: 01/27/2010] [Accepted: 01/31/2010] [Indexed: 11/26/2022]
Abstract
Sialoblastoma is a very rare congenital salivary gland tumor. No consensus has been reached concerning the treatment of this tumor due to its rarity. The treatment of reference is surgery, which can be mutilating, in the case of a locally invasive tumor. The treatment of metastatic disease is also controversial. The authors report a new case of a 6-year-old girl with a progressively growing left parotid mass since birth. The first cytological diagnosis was that of pleomorphic adenoma. Due to local progression, superficial parotidectomy was performed at the age of 3.5 years and revealed a diagnosis of sialoblastoma. Six months later, local recurrence and lung metastasis were treated by neoadjuvant chemotherapy with a very good partial response on the local recurrence and the lung metastasis, allowing complete parotidectomy with sacrifice of the facial nerve. Bilateral lung biopsies after adjuvant chemotherapy showed total necrosis. No recurrence was observed with a follow-up of 1 year. This case and a review of the literature confirm the very good chemosensitivity of this tumor and argue in favor of neoadjuvant chemotherapy for locally invasive tumors rather than extensive mutilating surgery.
Collapse
Affiliation(s)
- M Prigent
- ENT Department, Robert Debré-Assistance Publique Hospital, 48 rue Serurier, 75019 Paris, France.
| | | | | | | | | | | | | |
Collapse
|
4
|
Rousset E, Durand B, Champion J, Prigent M, Dufour P, Forfait C, Marois M, Gasnier T, Duquesne V, Thiéry R, Aubert M. Efficiency of a phase 1 vaccine for the reduction of vaginal Coxiella burnetii shedding in a clinically affected goat herd. Clin Microbiol Infect 2009; 15 Suppl 2:188-9. [DOI: 10.1111/j.1469-0691.2008.02220.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
5
|
Gonnord P, Delarasse C, Auger R, Benihoud K, Prigent M, Cuif MH, Lamaze C, Kanellopoulos JM. Palmitoylation of the P2X7 receptor, an ATP-gated channel, controls its expression and association with lipid rafts. FASEB J 2008; 23:795-805. [PMID: 18971257 DOI: 10.1096/fj.08-114637] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The P2X7 receptor (P2X7R) is an ATP-gated cationic channel expressed by hematopoietic, epithelial, and neuronal cells. Prolonged ATP exposure leads to the formation of a nonselective pore, which can result in cell death. We show that P2X7R is associated with detergent-resistant membranes (DRMs) in both transfected human embryonic kidney (HEK) cells and primary macrophages independently from ATP binding. The DRM association requires the posttranslational modification of P2X7R by palmitic acid. Treatment of cells with the palmitic acid analog 2-bromopalmitate as well as mutations of cysteine to alanine residues abolished P2X7R palmitoylation. Substitution of the 17 intracellular cysteines of P2X7R revealed that 4 regions of the carboxyl terminus domain are involved in palmitoylation. Palmitoylation-defective P2X7R mutants showed a dramatic decrease in cell surface expression because of their retention in the endoplasmic reticulum and proteolytic degradation. Taken together, our data demonstrate that P2X7R palmitoylation plays a critical role in its association with the lipid microdomains of the plasma membrane and in the regulation of its half-life.
Collapse
Affiliation(s)
- P Gonnord
- Institut de Biochimie et Biophysique Moléculaire et Cellulaire, CNRS UMR 8619, Université Paris Sud, F-91405 Orsay cedex, France
| | | | | | | | | | | | | | | |
Collapse
|
6
|
|
7
|
Goldenberg E, Prigent M, Caillod J. Dépollution des gaz d'échappement des moteurs diesel au moyen de pots catalytiques. ACTA ACUST UNITED AC 2006. [DOI: 10.2516/ogst:1983049] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
8
|
Prigent M, Barlat I, Langen H, Dargemont C. IkappaBalpha and IkappaBalpha /NF-kappa B complexes are retained in the cytoplasm through interaction with a novel partner, RasGAP SH3-binding protein 2. J Biol Chem 2000; 275:36441-9. [PMID: 10969074 DOI: 10.1074/jbc.m004751200] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
IkappaBalpha inhibits the transcriptional activity of NF-kappaB both in the cytoplasm by preventing the nuclear translocation of NF-kappaB and in the nucleus where it dissociates NF-kappaB from DNA and transports it back to the cytoplasm. Cytoplasmic localization of inactive NF-kappaB/IkappaBalpha complexes is controlled by mutual masking of nuclear import sequences of NF-kappaB p65 and IkappaBalpha and active CRM1-mediated nuclear export. Here, we describe an additional mechanism accounting for the cytoplasmic anchoring of IkappaBalpha or NF-kappaB/IkappaBalpha complexes. The N-terminal domain of IkappaBalpha contains a sequence responsible for the cytoplasmic retention of IkappaBalpha that is specifically recognized by G3BP2, a cytoplasmic protein that interacts with both IkappaBalpha and IkappaBalpha/NF-kappaB complexes. G3BP2 is composed of an N-terminal domain homologous to the NTF2 protein, followed by an acidic domain sufficient for the interaction with the IkappaBalpha cytoplasmic retention sequence, a region containing five PXXP motifs and a C-terminal domain containing RNA-binding motifs. Overexpression of G3BP2 directly promotes retention of IkappaBalpha in the cytoplasm, indicating that subcellular distribution of IkappaBalpha and NF-kappaB/IkappaBalpha complexes likely results from a equilibrium between nuclear import, nuclear export, and cytoplasmic retention. The molecular organization of G3BP2 suggests that this putative scaffold protein might connect the NF-kappaB signal transduction cascade with cellular functions such as nuclear transport or RNA metabolism.
Collapse
Affiliation(s)
- M Prigent
- Laboratoire de Transport Nucleocytoplasmique, Institut Curie-CNRS UMR144, 26 rue d'Ulm, 75248 Paris Cedex 05, France
| | | | | | | |
Collapse
|
9
|
Abstract
Nanometre-sized carbon fibres across holes have been observed in a lensless point projection field-emission microscope operating between 100 and 300 eV. At sufficiently high magnification fringe patterns appear; with the help of simulations we show that they are strongly dependent on the charge density of the fibres. These patterns are characterized by an odd number of fringes with a central fringe that becomes very bright as the charge increases. Average diameter and linear charge density have been obtained with remarkable precision from analysis of fringes. Charge distribution from the middle to the edge of fibres has been investigated as well as narrowings at localized places on the fringe pattern. From these two examples, the limits of the models used for the simulations and those of the data acquisition system are discussed. Finally, this work emphasizes the fact that the fringe pattern masks the actual form of the fibre and that it is necessary to take account of the charge effect to interpret this diffraction pattern.
Collapse
Affiliation(s)
- M Prigent
- Laboratoire d'Electronique Nanotechnologies Capteurs, Universite Claude Bernard Lyon1, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne Cedex, France
| | | |
Collapse
|
10
|
Nallatamby JC, Prigent M, Vaury E, Laloue A, Camiade M, Obregon J. Low phase noise operation of microwave oscillator circuits. IEEE Trans Ultrason Ferroelectr Freq Control 2000; 47:411-420. [PMID: 18238558 DOI: 10.1109/58.827428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this paper, we describe a theoretical basis, leading to new results, on the general conditions to be fulfilled by oscillator circuits to achieve a very low phase noise. Three main conditions must be fulfilled by a transistor oscillator circuit to reach the minimum phase noise. The energy stored in the resonator must be maximum. Its transfer to the controlling voltage port of the transistor current source must be first maximized. A possible conversion noise at the transistor output port will be also minimized by maximizing the energy transferred to that port. The proposed method has been applied to an experimental oscillator set up with a PHEMT transistor. A state-of-the-art phase noise of -80 dBc/Hz at 100 Hz offset from carrier with a 1/f(3) slope has been measured at room temperature with a 9.2 GHz, oscillator. The application of these new results to free-running oscillator circuits with one-stage then multistage transistor amplifiers demonstrate clearly the validity of the design method. The efficiency of this design method and its ease of use represent a real breakthrough in the field of low noise transistor oscillator circuit design.
Collapse
|
11
|
Dubien C, Schweich D, Mabilon G, Martin B, Prigent M. Three-way catalytic converter modelling: fast- and slow-oxidizing hydrocarbons, inhibiting species, and steam-reforming reaction. Chem Eng Sci 1998. [DOI: 10.1016/s0009-2509(97)00313-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
12
|
Abstract
Eukaryotic chromosomes are ponctuated by specialized DNA sequences (MARs) characterized by their ability to bind the network of nonhistone proteins that form the nuclear matrix or scaffold. We previously described an amplifiable cluster of genes with different tissue-specific expression patterns, located on Chinese hamster chromosome 1q. This model is especially appropriate to study the relationships between MARs and transcription units. We show here that four attachment regions, with sequences exhibiting motifs specific to MARs, are present within the 100 kb of screened DNA. Three of them are relatively short sequences localized in intergenic regions. The last one extends over one of the transcription units and contains a region previously identified as a recombination hot spot. Moreover, the analysis of a DNA sequence extending over some 50 Kb of this region and spanning at least four genes, disclosed a strikingly sharp change in G + C content. This strongly suggests that the studied region contains the boundary of two isochores. We propose that the frequency and the size of MARs are correlated to their localization in G + C rich or poor domains.
Collapse
Affiliation(s)
- M A Fernandez
- Unitéde Génétique Somatique (URA CNRS 1960), Institut Pasteur, Paris, France
| | | | | | | | | | | |
Collapse
|
13
|
Pardanaud L, Luton D, Prigent M, Bourcheix LM, Catala M, Dieterlen-Lievre F. Two distinct endothelial lineages in ontogeny, one of them related to hemopoiesis. Development 1996; 122:1363-71. [PMID: 8625825 DOI: 10.1242/dev.122.5.1363] [Citation(s) in RCA: 234] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have shown previously by means of quail/chick transplantations that external and visceral organs, i.e., somatopleural and splanchnopleural derivatives, acquire their endothelial network through different mechanisms, namely immigration (termed angiogenesis) versus in situ emergence of precursors (or vasculogenesis). We have traced the distribution of QH1-positive cells in chick hosts after replacement of the last somites by quail somites (orthotopic grafts) or lateral plate mesoderm (heterotopic grafts). The results lead to the conclusion that the embryo becomes vascularized by endothelial precursors from two distinct regions, splanchnopleural mesoderm and paraxial mesoderm. The territories respectively vascularized are complementary, precursors from the paraxial mesoderm occupy the body wall and kidney, i.e., they settle along with the other paraxial mesoderm derivatives and colonize the somatopleure. The precursors from the two origins have distinct recognition and potentialities properties: endothelial precursors of paraxial origin are barred from vascularizing visceral organs and from integrating into the floor of the aorta, and are never associated with hemopoiesis; splanchnopleural mesoderm grafted in the place of somites, gives off endothelial cells to body wall and kidney but also visceral organs. It gives rise to hemopoietic precursors in addition to endothelial cells.
Collapse
Affiliation(s)
- L Pardanaud
- Institut d'Embryologie Cellulaire et Moleculaire du CNRS, Nogent-sur-Marne, France
| | | | | | | | | | | |
Collapse
|
14
|
Coq B, Tachon D, Figu�ras F, Mabilon G, Prigent M. Influence of operating protocol in the temperature-programmed reaction of NO with decane on Cu/mordenite. Catal Letters 1995. [DOI: 10.1007/bf00807016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
15
|
|
16
|
Weibel M, Garin F, Bernhardt P, Maire G, Prigent M. Influence of water in the activity of catalytic converters. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/s0167-2991(08)62979-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
|
17
|
Metges PJ, Delahaye RP, Mine PJ, Kleitz C, Prigent M. [Apophyseal detachment of the anterior iliac spines: a radiological study of three cases (author's transl)]. J Radiol 1979; 60:251-4. [PMID: 490470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The authors describe 3 cases of apophyseal detachment of the anterior iliac spines. This traumatic affection occurs mainly in adolescents during sporting activities, and is a rare disorder. It has to be borne in mind when a more or less typical clinical picture is present, and the diagnosis can be made by radiological examination.
Collapse
|