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Gallego JA, Dideriksen JL, Farina D, Rocon E, Holobar A, Pons JL. A modelling study on transmission of the central oscillator in tremor by a motor neuron pool. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2011:2037-40. [PMID: 22254736 DOI: 10.1109/iembs.2011.6090375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In spite of decades of intense research, pathological tremors still constitute unknown disorders. This study addresses, based on a multi-scale model, the behavior of an entire pool of motor neurons in tremor, under the hypothesis that tremor is an oscillation of central origin commonly projected to all motor neurons that innervate a muscle. Our results show that under such conditions both paired discharges and enhanced motor neuron synchronization, two of the characteristic landmarks of tremor, emerge. Moreover, coherence and correlation analyses suggest that the central tremor oscillator is transmitted linearly by the motor neuron pool given that a small set (7 or 8) of motor neurons are sampled.
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Torricelli D, Aleixandre M, Alguacil Diego IM, Cano De La Cuerda R, Molina Rueda F, Carratala Tejada M, Piazza S, Pons JL. Modular control of mediolateral postural sway. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2012:3632-3635. [PMID: 23366714 DOI: 10.1109/embc.2012.6346753] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Is voluntary motor control of mediolateral rhythmic sway ruled by modular organization? Answering this question has potential implications in diagnosis and rehabilitation of neurologically impairments. Superficial EMG and computerized dynamic posturography has been used in this study to investigate modular control of six healthy subjects. Postural movements have been performed at three different frequencies to also test the influence of speed on the composition of synergies and activations. Results showed that two synergies account for more than 75% of EMG variance and are shared by all subjects across all frequency conditions. These evidences, together with a functional interpretation of computed muscle synergies, support the existence of consistent modular control across healthy subjects during mediolateral voluntary movements.
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del-Ama AJ, Moreno JC, Gil-Agudo A, de-los-Reyes A, Pons JL. Online assessment of human-robot interaction for hybrid control of walking. SENSORS 2011; 12:215-25. [PMID: 22368465 PMCID: PMC3279209 DOI: 10.3390/s120100215] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 12/07/2011] [Accepted: 12/16/2011] [Indexed: 11/16/2022]
Abstract
Restoration of walking ability of Spinal Cord Injury subjects can be achieved by different approaches, as the use of robotic exoskeletons or electrical stimulation of the user's muscles. The combined (hybrid) approach has the potential to provide a solution to the drawback of each approach. Specific challenges must be addressed with specific sensory systems and control strategies. In this paper we present a system and a procedure to estimate muscle fatigue from online physical interaction assessment to provide hybrid control of walking, regarding the performances of the muscles under stimulation.
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Belda-Lois JM, Mena-del Horno S, Bermejo-Bosch I, Moreno JC, Pons JL, Farina D, Iosa M, Molinari M, Tamburella F, Ramos A, Caria A, Solis-Escalante T, Brunner C, Rea M. Rehabilitation of gait after stroke: a review towards a top-down approach. J Neuroeng Rehabil 2011; 8:66. [PMID: 22165907 PMCID: PMC3261106 DOI: 10.1186/1743-0003-8-66] [Citation(s) in RCA: 263] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Accepted: 12/13/2011] [Indexed: 01/19/2023] Open
Abstract
This document provides a review of the techniques and therapies used in gait rehabilitation after stroke. It also examines the possible benefits of including assistive robotic devices and brain-computer interfaces in this field, according to a top-down approach, in which rehabilitation is driven by neural plasticity.The methods reviewed comprise classical gait rehabilitation techniques (neurophysiological and motor learning approaches), functional electrical stimulation (FES), robotic devices, and brain-computer interfaces (BCI).From the analysis of these approaches, we can draw the following conclusions. Regarding classical rehabilitation techniques, there is insufficient evidence to state that a particular approach is more effective in promoting gait recovery than other. Combination of different rehabilitation strategies seems to be more effective than over-ground gait training alone. Robotic devices need further research to show their suitability for walking training and their effects on over-ground gait. The use of FES combined with different walking retraining strategies has shown to result in improvements in hemiplegic gait. Reports on non-invasive BCIs for stroke recovery are limited to the rehabilitation of upper limbs; however, some works suggest that there might be a common mechanism which influences upper and lower limb recovery simultaneously, independently of the limb chosen for the rehabilitation therapy. Functional near infrared spectroscopy (fNIRS) enables researchers to detect signals from specific regions of the cortex during performance of motor activities for the development of future BCIs. Future research would make possible to analyze the impact of rehabilitation on brain plasticity, in order to adapt treatment resources to meet the needs of each patient and to optimize the recovery process.
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Moreno JC, del Ama AJ, de los Reyes-Guzmán A, Gil-Agudo Á, Ceres R, Pons JL. Neurorobotic and hybrid management of lower limb motor disorders: a review. Med Biol Eng Comput 2011; 49:1119-30. [DOI: 10.1007/s11517-011-0821-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 07/30/2011] [Indexed: 10/17/2022]
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Abstract
Exoskeletons are wearable robots exhibiting a close cognitive and physical interaction with the human user. These are rigid robotic exoskeletal structures that typically operate alongside human limbs. Scientific and technological work on exoskeletons began in the early 1960s but have only recently been applied to rehabilitation and functional substitution in patients suffering from motor disorders. Key topics for further development of exoskeletons in rehabilitation scenarios include the need for robust human-robot multimodal cognitive interaction, safe and dependable physical interaction, true wearability and portability, and user aspects such as acceptance and usability. This discussion provides an overview of these aspects and draws conclusions regarding potential future research directions in robotic exoskeletons.
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Rocon E, Gallego JA, Barrios L, Victoria AR, Ibanez J, Farina D, Negro F, Dideriksen JL, Conforto S, D'Alessio T, Severini G, Belda-Lois JM, Popovic LZ, Grimaldi G, Manto M, Pons JL. Multimodal BCI-mediated FES suppression of pathological tremor. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2011; 2010:3337-40. [PMID: 21097230 DOI: 10.1109/iembs.2010.5627914] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Tremor constitutes the most common movement disorder; in fact 14.5% of population between 50 to 89 years old suffers from it. Moreover, 65% of patients with upper limb tremor report disability when performing their activities of daily living (ADL). Unfortunately, 25% of patients do not respond to drugs or neurosurgery. In this regard, TREMOR project proposes functional compensation of upper limb tremors with a soft wearable robot that applies biomechanical loads through functional electrical stimulation (FES) of muscles. This wearable robot is driven by a Brain Neural Computer Interface (BNCI). This paper presents a multimodal BCI to assess generation, transmission and execution of both volitional and tremorous movements based on electroencephalography (EEG), electromyography (EMG) and inertial sensors (IMUs). These signals are combined to obtain: 1) the intention to perform a voluntary movement from cortical activity (EEG), 2) tremor onset, and an estimation of tremor frequency from muscle activation (EMG), and 3) instantaneous tremor amplitude and frequency from kinematic measurements (IMUs). Integration of this information will provide control signals to drive the FES-based wearable robot.
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Frizera Neto A, Gallego JA, Rocon E, Pons JL, Ceres R. Extraction of user's navigation commands from upper body force interaction in walker assisted gait. Biomed Eng Online 2010; 9:37. [PMID: 20687921 PMCID: PMC2924341 DOI: 10.1186/1475-925x-9-37] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Accepted: 08/05/2010] [Indexed: 11/10/2022] Open
Abstract
Background The advances in technology make possible the incorporation of sensors and actuators in rollators, building safer robots and extending the use of walkers to a more diverse population. This paper presents a new method for the extraction of navigation related components from upper-body force interaction data in walker assisted gait. A filtering architecture is designed to cancel: (i) the high-frequency noise caused by vibrations on the walker's structure due to irregularities on the terrain or walker's wheels and (ii) the cadence related force components caused by user's trunk oscillations during gait. As a result, a third component related to user's navigation commands is distinguished. Results For the cancelation of high-frequency noise, a Benedict-Bordner g-h filter was designed presenting very low values for Kinematic Tracking Error ((2.035 ± 0.358)·10-2 kgf) and delay ((1.897 ± 0.3697)·101ms). A Fourier Linear Combiner filtering architecture was implemented for the adaptive attenuation of about 80% of the cadence related components' energy from force data. This was done without compromising the information contained in the frequencies close to such notch filters. Conclusions The presented methodology offers an effective cancelation of the undesired components from force data, allowing the system to extract in real-time voluntary user's navigation commands. Based on this real-time identification of voluntary user's commands, a classical approach to the control architecture of the robotic walker is being developed, in order to obtain stable and safe user assisted locomotion.
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Combe ML, Pons JL, Sesboue R, Martin JP. Electrophoretic transfer from polyacrylamide gel to nitrocellulose sheets, a new method to characterize multilocus enzyme genotypes of Klebsiella strains. Appl Environ Microbiol 2010; 60:26-30. [PMID: 16349155 PMCID: PMC201264 DOI: 10.1128/aem.60.1.26-30.1994] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A new method for multilocus enzyme electrophoresis, based on electrophoretic transfers to nitrocellulose after polyacrylamide-agarose gel electrophoresis was explored. Electrophoretic separation was performed on 1-mm-thick slab gels with 6-mul samples of bacterial extracts and was followed by serial 5-min consecutive transfers. The transferability of 19 metabolic enzymes of Klebsiella strains was studied and allowed the simultaneous examination of one enzyme in the separation gel and at least five enzymes on nitrocellulose sheets. The resolution of enzyme bands was increased on nitrocellulose; thus, well-separated bands were recorded for nucleoside phosphorylase, peptidase, and phosphoglucose isomerase whereas their mobility variants could not be clearly distinguished in the separation gel because of stain diffusion. The study of genetic relationships of 42 strains of Klebsiella pneumoniae and 24 strains of Klebsiella oxytoca demonstrated the reliability of the method, since clustering analysis of electrophoretic types, based on electrophoretic polymorphism of 10 metabolic enzymes, showed two main clusters well correlated with the two species. The 57 electrophoretic types described confirm the usefulness of the method for the study of genetic relationships between closely related strains.
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Pons JL, Barrios LJ, Azorín JM. Editorial. Appl Bionics Biomech 2009. [DOI: 10.1080/11762320903105507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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61
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Moreno JC, Brunetti F, Navarro E, Forner-Cordero A, Pons JL. Analysis of the human interaction with a wearable lower-limb exoskeleton. Appl Bionics Biomech 2009. [DOI: 10.1080/11762320902823324] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Rocon E, Pons JL, Andrade AO, Nasuto SJ. Application of EMD as a novel technique for the study of tremor time series. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2008; Suppl:6533-6. [PMID: 17959445 DOI: 10.1109/iembs.2006.260871] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This paper introduces the Hilbert Analysis (HA), which is a novel digital signal processing technique, for the investigation of tremor. The HA is formed by two complementary tools, i.e. the Empirical Mode Decomposition (EMD) and the Hilbert Spectrum (HS). In this work we show that the EMD can automatically detect and isolate tremulous and voluntary movements from experimental signals collected from 31 patients with different conditions. Our results also suggest that the tremor may be described by a new class of mathematical functions defined in the HA framework. In a further study, the HS was employed for visualization of the energy activities of signals. This tool introduces the concept of instantaneous frequency in the field of tremor. In addition, it could provide, in a time-frequency-energy plot, a clear visualization of local activities of tremor energy over the time. The HA demonstrated to be very useful to perform objective measurements of any kind of tremor and can therefore be used to perform functional assessment.
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Forner-Cordero A, Mateu-Arce M, Forner-Cordero I, Alcántara E, Moreno JC, Pons JL. Study of the motion artefacts of skin-mounted inertial sensors under different attachment conditions. Physiol Meas 2008; 29:N21-31. [PMID: 18401071 DOI: 10.1088/0967-3334/29/4/n01] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A common problem shared by accelerometers, inertial sensors and any motion measurement method based on skin-mounted sensors is the movement of the soft tissues covering the bones. The aim of this work is to propose a method for the validation of the attachment of skin-mounted sensors. A second-order (mass-spring-damper) model was proposed to characterize the behaviour of the soft tissue between the bone and the sensor. Three sets of experiments were performed. In the first one, different procedures to excite the system were evaluated to select an adequate excitation stimulus. In the second one, the selected stimulus was applied under varying attachment conditions while the third experiment was used to test the model. The heel drop was chosen as the excitation method because it showed lower variability and could discriminate between different attachment conditions. There was, in agreement with the model, a trend to increase the natural frequency of the system with decreasing accelerometer mass. An important result is the development of a standard procedure to test the bandwidth of skin-mounted inertial sensors, such as accelerometers mounted on the skin or markers heavier than a few grams.
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Brunetti F, Moreno JC, Ruiz AF, Rocon E, Pons JL. A new platform based on IEEE802.15.4 wireless inertial sensors for motion caption and assessment. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; Suppl:6497-500. [PMID: 17959435 DOI: 10.1109/iembs.2006.260866] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Systems for motion caption and assessment in biomechanics are mostly based on photogrammetry. These systems are restricted to the movement analysis lab and moreover, they are very expensive. New advances in MEMs (Microelectromechanical) and wireless technologies enable inertial sensing as an alternatives for motion caption. This paper presents a wireless inertial sensor including 3 linear accelerometers, 3 gyroscopes and 3 magnetometers. The IMU (inertial measurement unit) includes a IEEE802.15.4 compliant transceiver. The platform expands the frontiers of movement analysis for motion caption in real scenarios like sports and wearable robotics since it does not need structurated labs. Besides the advantages, the cost of the platform is much lower comparing actual photogrammetry systems.
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Rocon E, Belda-Lois JM, Ruiz AF, Manto M, Moreno JC, Pons JL. Design and validation of a rehabilitation robotic exoskeleton for tremor assessment and suppression. IEEE Trans Neural Syst Rehabil Eng 2007; 15:367-78. [PMID: 17894269 DOI: 10.1109/tnsre.2007.903917] [Citation(s) in RCA: 238] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Exoskeletons are mechatronic systems worn by a person in such a way that the physical interface permits a direct transfer of mechanical power and exchange of information. Upper limb robotic exoskeletons may be helpful for people with disabilities and/or limb weakness or injury. Tremor is the most common movement disorder in neurological practice. In addition to medication, rehabilitation programs, and deep brain stimulation, biomechanical loading has appeared as a potential tremor suppression alternative. This paper introduces the robotic exoskeleton called WOTAS (wearable orthosis for tremor assessment and suppression) that provides a means of testing and validating nongrounded control strategies for orthotic tremor suppression. This paper describes in detail the general concept for WOTAS, outlining the special features of the design and selection of system components. Two control strategies developed for tremor suppression with exoskeletons are described. These two strategies are based on biomechanical loading and notch filtering the tremor through the application of internal forces. Results from experiments using these two strategies on patients with tremor are summarized. Finally, results from clinical trials are presented, which indicate the feasibility of ambulatory mechanical suppression of tremor.
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Leflon-Guibout V, Pons JL, Heym B, Nicolas-Chanoine MH. Typing of Clostridium perfringens strains by use of Random Amplified Polymorphic DNA (RAPD) system in comparison with zymotyping. Anaerobe 2007; 3:245-50. [PMID: 16887598 DOI: 10.1006/anae.1997.0094] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/1997] [Accepted: 04/03/1997] [Indexed: 11/22/2022]
Abstract
The definition of strain clonality postulates that strains showed identical phenotypic and genetic traits are likely to descend from a common ancestor even if they were isolated from different sources and locations. Regarding this definition, non-epidemiologically linked strains might be clonal strains. To overcome this ambiguity, the discriminatory capability of RAPD typing was assessed firstly on eight Clostridium perfringens strains proven to be chromosomally different with one being the mutant of another one. Thirteen primers were tested but only two were able to differentiate seven of the eight strains. With none of the used primers it was possible to differentiate the parental strain and its mutant harboring an insertion of 180 kb. The four most discriminant primers were retained to determine the RAPD fingerprints of a further 20 previously zymotyped strains from which seventeen were unrelated. To compare the two typing systems, the zymotype of the eight chromosomally different strains was determined. Thus, the discriminatory index was calculated on the basis of 25 unrelated C. perfringens strains. This was 0.97 with RAPD typing and 0.99 with zymotyping. From these results we conclude that the RAPD typing which is less fastidious than zymotyping can be used as an epidemiological marker for C. perfringens.
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Moreno J, Brunetti F, Pons JL. An autonomous control and monitoring system for lower limb orthosis: the gait project case. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:2125-8. [PMID: 17272143 DOI: 10.1109/iembs.2004.1403623] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
A wearable control and monitoring system has been developed for a novel active orthotic device. The development addresses the need of an autonomous tool for gait analysis during normal use of the orthotic device. The system has two basic components: the base unit and the ambulatory Uniu. The units communicate by means of a Bluetooth link. In order to test the system, a knee-ankle-foot orthosis has been instrumented for gait control and monitoring of biomechanical and comfort data during daily use by patients with muscular deficiencies. This paper describes the system developed, outlines its performance and presents measurements recorded while performing different activities.
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Brunetti FJ, Rocon E, Pons JL, Manto M. The tremor coherence analyzer (TCA): a portable tool to assess instantaneous inter-muscle coupling in tremor. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2006:61-4. [PMID: 17271603 DOI: 10.1109/iembs.2004.1403090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
This paper proposes a novel system for pathological tremor study and diagnosis. The system described called TCA (tremor coherence analyzer) is based on a electronic device developed for wireless monitoring of physiological variables. The device uses Bluetooth technology to communicate. The proposed technique for pathological tremor analysis uses surface EMG signals. The EMG sensors are located on forearm muscles to measure muscular activity due to pathological tremor. The coherence function between these signals is calculated. The application of the coherence function allows to determine linear dependencies between two signals.
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Ceres R, Pons JL, Calderón L, Jiménez AR, Azevedo L. A robotic vehicle for disabled children. Providing assisted mobility with the PALMA project. ACTA ACUST UNITED AC 2006; 24:55-63. [PMID: 16382806 DOI: 10.1109/memb.2005.1549731] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Pons JL, Malliavin TE, Tramesel D, Delsuc MA. NMRb: a web-site repository for raw NMR datasets. Bioinformatics 2004; 20:3707-9. [PMID: 15284093 DOI: 10.1093/bioinformatics/bth450] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
UNLABELLED The development of NMR in structural proteomics requires the availability of automatic structure determination methods. Many researchers are commonly confronted with the lack of raw datasets during the validation step of such methods. In order to increase test possibilities, the NMRb web-site offers a database of NMR raw datasets, ordered by spectral characteristics. AVAILABILITY NMRb is available from: http://nmrb.cbs.cnrs.fr. SUPPLEMENTARY INFORMATION General organization of NMRb figure, relational model organization, and XML structure files are available from http://nmrb.cbs.cnrs.fr/nmrb-doc.html.
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Pons JL, Rodríguez H, Ceres R, Calderón L. Novel modeling technique for the stator of traveling wave ultrasonic motors. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2003; 50:1429-1435. [PMID: 14682626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Traveling wave ultrasonic motors (TWUM) are a promising type of piezoelectric transducers, which are based on the friction transmission of mechanical propagating waves. These waves are excited on the stator by using high Q piezoelectric ceramics. This article presents a modeling strategy, which allows for a quick and precise modal and forced analysis of the stator of TWUM. First-order shear deformation laminated plate theory is applied to annular subdomains (super-elements) of the stator. In addition to shear deformations, the model takes into account the effect of rotary inertia, the stiffness contribution of the teeth, and the linear varying thickness of the stator. Moreover, the formulation considers a more realistic function for the electric field inside the piezoelectric ceramic, i.e., a linear function, instead of the generally assumed constant electric field. The Ritz method is used to find an approximated solution for the dynamic equations. Finally, the modal response is obtained and compared against the results from classical simplified models and the finite element method. Thus, the high accuracy and short computation times of the novel strategy were demonstrated.
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Pons JL, Rodríguez H, Luyckx I, Reynaerts D, Ceres R, Van Brussel H. High torque ultrasonic motors for hand prosthetics: current status and trends. Technol Health Care 2002; 10:121-33. [PMID: 12082216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
This paper presents the work carried out at the Instituto de Automática Industrial, in the framework of the EU MANUS project and with the co-operation of the Katholieke Universiteit of Leuven, to develop a specifically designed TWUM for driving our prototype of hand prosthesis. The application of TWUM to prosthetic devices has clear advanteges, namely, noiseless operation, self-braking drive, high torque and low speed characteristics. Here we analyse main actuation advantages, point out main drawbacks of this technology and describe our research in the area of specific design of TWUM for high torque actuation, improved control characteristics and enhanced overall performance. We intend to provide a concurrent approach to the overall actuator design involving electronics, mechanical design as well as improved control strategies having in mind the prosthetic application.
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Etienne M, Gueit I, Abboud P, Pons JL, Jacquot S, Caron F. Fusobacterium nucleatum hepatic abscess with pylephlebitis associated with idiopathic CD4(+) T lymphocytopenia. Clin Infect Dis 2001; 32:326-8. [PMID: 11170936 DOI: 10.1086/318468] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Combe ML, Pons JL. Genetic relationships within the genus Prevotella analyzed by multilocus enzyme electrophoresis and DNA-DNA hybridization. Syst Appl Microbiol 1999; 22:596-603. [PMID: 10794148 DOI: 10.1016/s0723-2020(99)80013-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The genetic diversity and relationships within the genus Prevotella were studied by analyzing twenty-five strains by multilocus enzyme electrophoresis (MLEE) at nine metabolic enzyme loci and DNA-DNA hybridization. MLEE revealed a high genetic diversity with 25 electrophoretic types (ETs) for the 25 strains studied, a mean number of alleles per enzyme locus of 6.8 and a mean genetic diversity per locus of 0.786. The index of association described by Maynard Smith et al. (1993) revealed a clonal structure within the genus Prevotella. A dendrogram generated by cluster analysis of a matrix of ETs showed that species like P. bivia, P. buccae, P. oris, P. oralis, P. nigrescens, and P. denticola form clusters that are consistent with DNA homologies. However, strains identified as P. melaninogenica or P. loescheii by DNA-DNA hybridization did not constitute distinct subpopulations in MLEE. MLEE analysis demonstrated its high power in differentiating closely related strains. It provides an alternative to 16S rRNA analysis for the study of phylogenetic relationships within the genus Prevotella, especially for differentiating strains with high DNA homology or high rRNA homology.
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Pons JL, Delsuc MA. RESCUE: an artificial neural network tool for the NMR spectral assignment of proteins. JOURNAL OF BIOMOLECULAR NMR 1999; 15:15-26. [PMID: 10549132 DOI: 10.1023/a:1008338605320] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The assignment of the 1H spectrum of a protein or a polypeptide is the prerequisite for advanced NMR studies. We present here an assignment tool based on the artificial neural network technology, which determines the type of the amino acid from the chemical shift values observed in the 1H spectrum. Two artificial neural networks have been trained and extensively tested against a non-redundant subset of the BMRB chemical shift data bank [Seavey, B.R. et al. (1991) J. Biomol. NMR, 1, 217-236]. The most promising of the two accomplishes the analysis in two steps, grouping related amino acids together. It presents a mean rate of success above 80% on the test set. The second network tested separates down to the single amino acid; it presents a mean rate of success of 63%. This tool has been used to assist the manual assignment of peptides and proteins and can also be used as a block in an automated approach to assignment. The program has been called RESCUE and is made publicly available at the following URL: http:(/)/www.infobiosud.univ-montp1.fr/rescue.
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Pestel-Caron M, Graff G, Berthelot G, Pons JL, Lemeland JF. Molecular analysis of Mycobacterium avium isolates by using pulsed-field gel electrophoresis and PCR. J Clin Microbiol 1999; 37:2450-5. [PMID: 10405383 PMCID: PMC85252 DOI: 10.1128/jcm.37.8.2450-2455.1999] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Genetic relationships among 46 isolates of Mycobacterium avium recovered from 37 patients in a 2,500-bed hospital from 1993 to 1998 were assessed by pulsed-field gel electrophoresis (PFGE) and PCR amplification of genomic sequences located between the repetitive elements IS1245 and IS1311. Each technique enabled the identification of 27 to 32 different patterns among the 46 isolates, confirming that the genetic heterogeneity of M. avium strains is high in a given community. Furthermore, this retrospective analysis of sporadic isolates allowed us (i) to suggest the existence of two remanent strains in our region, (ii) to raise the question of the possibility of nosocomial acquisition of M. avium strains, and (iii) to document laboratory contamination. The methods applied in the present study were found to be useful for the typing of M. avium isolates. In general, both methods yielded similar results for both related and unrelated isolates. However, the isolates in five of the six PCR clusters were distributed among two to three PFGE patterns, suggesting that this PCR-based method may have limitations for the analysis of strains with low insertion sequence copy numbers or for resolution of extended epidemiologic relationships.
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Malliavin TE, Pons JL, Delsuc MA. An NMR assignment module implemented in the Gifa NMR processing program. Bioinformatics 1998; 14:624-31. [PMID: 9730928 DOI: 10.1093/bioinformatics/14.7.624] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
MOTIVATION Peptide and protein structures are determined daily using NMR spectroscopy. Assignment of the NMR spectra is an important step within the procedure and is usually the limiting one. Computer-aided assignment tools should be user friendly with open architecture to communicate with other programs involved in the structure determination. RESULTS Here we present an interactive NMR assignment module which provides numerous graphic tools for the user. The module is composed of a database management system-handling peaks, spins and spin-systems. The assignment information is maintained as a set of interrelated associative arrays, which serve as generic high-level data structures. The module is developed in the macro language embedded in the Gifa NMR processing program (Pons et al. , J. Biomol. NMR, 8 , 445-452, 1996). This provides the user with a consistent interface, a set of sophisticated tools, and an easily extendible and customizable environment. AVAILABILITY The program is available on request from the authors. The Gifa package can be accessed at: ((http://www.cbs. univ-montp1.fr/GIFA)) CONTACT: Marc-Andre.Delsuc@cbs.univ-montp1.fr
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Pons JL, Mandement MN, Martin E, Lemort C, Nouvellon M, Mallet E, Lemeland JF. Clonal and temporal patterns of nasopharyngeal penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae stains in children attending a day care center. J Clin Microbiol 1996; 34:3218-22. [PMID: 8940477 PMCID: PMC229488 DOI: 10.1128/jcm.34.12.3218-3222.1996] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The nasopharyngeal carriage of penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae (PSSp and PRSp, respectively) was analyzed in 116 children attending a day care center in Rouen, France, by three observation periods in November, January, and March of the winter of 1993 to 1994. The carriage rate of S. pneumoniae was found to be 47.7, 47.3, and 49.6% at each different observation period, and PRSp accounted for 42.2, 40.3, and 40.6% of pneumococcal isolates, respectively. The 52 isolates recovered in November were distributed in 34 electrophoretic types (ETs) by multilocus enzyme electrophoresis; 15 PRSp isolates, all of serotype 23F, belonged to a clonal complex of five ETs, representing the dominant population of PRSp in November. The temporal pattern of S. pneumoniae carriage was studied in 17 children who were colonized at the three periods by multilocus enzyme analysis of their isolates. The PSSp isolated, exhibiting distinct ETs, were transient only among these day care attendees. In contrast, most of the PRSp isolated in January and March belonged to the clonal complex. Thus, this PRSp population was resident in the day care center throughout the study period.
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Pons JL, Malliavin TE, Delsuc MA. Gifa V. 4: A complete package for NMR data set processing. JOURNAL OF BIOMOLECULAR NMR 1996; 8:445-452. [PMID: 20859778 DOI: 10.1007/bf00228146] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/1996] [Accepted: 08/09/1996] [Indexed: 05/29/2023]
Abstract
The Gifa program is designed for processing, displaying and analysing 1D, 2D and 3D NMR data sets. It has been constructed in a modular fashion, based on three independent modules: a set of commands that perform all the basic processing operations such as apodisation functions, a complete set of Fourier Transforms, phasing and baseline correction, peak-picking and line fitting, linear prediction and maximum entropy processing; a set of command language primitives that permit the execution of complex macro commands; and a set of graphic commands that permit to build a complete graphic user interface, allowing the user to interact easily with the program. We have tried to create a versatile program that can be easily extended according to the user's requirements and that is adapted to a novice as well as an experienced user. The program runs on any UNIX computer, with or without graphic display, in interactive or batch mode.
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Mangeney N, Bakkouch A, Pons JL, Dupeyron C, Niel P, Leluan G. Methicillin-resistant Staphylococcus aureus subtyping: interest of combined antibiotyping and esterase electrophoretic typing. THE JOURNAL OF APPLIED BACTERIOLOGY 1995; 79:347-51. [PMID: 7592126 DOI: 10.1111/j.1365-2672.1995.tb03147.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Ninety-four methicillin-resistant Staphylococcus aureus isolates (MRSA) were characterized by means of two typing methods, antibiotyping and esterase electrophoretic typing. Antibiotyping, recorded on the basis of susceptibility testing of 13 antimicrobial agents, allowed the description of 18 antibiotypes, four of which comprised 30, 14, 14 and 12 strains respectively. Esterase electrophoretic typing, based on esterase activity against seven synthetic substrates after polyacrylamide-agarose gel electrophoresis, led to the description of 12 electrophoretic types, two of which were predominant with 60 and 20 strains respectively. The combined use of both typing methods yielded 32 combinations, three of which were predominant with 21, 12 and 11 strains respectively. A good differentiation of strains was achieved, particularly when the antibiotype was correlated to the electrophoretic type. Thus, the combination of antibiotyping with esterase electrophoretic typing may be proposed as a well-suited method for the characterization of MRSA strains.
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Martin E, Nouvellon M, Pestel M, Pons JL, Lemeland JF. Evaluation of the Epsilometer test (E test) for testing the susceptibility of coagulase-negative staphylococci to teicoplanin. J Antimicrob Chemother 1995; 36:83-91. [PMID: 8537287 DOI: 10.1093/jac/36.1.83] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The antimicrobial susceptibilities of 118 clinical isolates of coagulase-negative staphylococci to teicoplanin were determined by disc diffusion and the Epsilometer test (E test) and the results were compared with the MICs determined by the agar dilution method of the National Committee for Clinical Laboratory Standards (NCCLS). There was a poor correlation of r = 0.5 between the zone diameters of inhibition and agar dilution MICs and 10 and four of the 11 isolates for which the MICs were > or = 32 mg/L were misclassified as susceptible by the disc test after applying the interpretative criteria of the NCCLS and the Comité de l'Antibiogramme de la Société Française de Microbiologie (CASFM), respectively. The E test tended to result in MICs that were lower than those determined by agar dilution and only 66% of MIC were within +/- 1 log2 dilution of each other. Only one of 11 resistant strains was detected by the E test and, although there was no false resistance, six resistant strains were misclassified as susceptible after applying the criteria of the NCCLS as were four such isolates when the criteria of the CASFM were employed, probably as a result of using too light an inoculum. Disc diffusion is not a reliable means of determining the susceptibility of coagulase-negative staphylococci but might be replaced by the E-test provided that discrepant results can be resolved by using a denser inoculum.
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Mangeney N, Bakkouch A, Royan F, Duault M, Pons JL, Dupeyron C, Niel P, Louarn F, Leluan G. [Outbreak of infections of Klebsiella pneumoniae with extended spectrum beta-lactamase in a hospital unit with a long and medium stay]. PATHOLOGIE-BIOLOGIE 1995; 43:336-342. [PMID: 7567126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Fourteen extended-spectrum beta-lactamase (ES beta la) Klebsiella pneumoniae strains were isolated from 14 inpatients between February 1993 and February 1994, in a medium- and long-stay neurological unit. For this reason an epidemiological study was begun, based on strain typing and examination of patient files. Strain typing was carried out by two methods (i) the analysis of antibiotic resistance, showing 7 different antibiotypes among the 14 strains studied, (ii) the analysis of esterase and dehydrogenase electrophoretic polymorphism in polyacrylamide-agarose gel. The method was checked by analysing 11 Klebsiella pneumoniae strains with wild phenotype for beta-lactam antibiotics, which were isolated during the same period in the same unit. Simultaneously 6 other strains isolated during the same period in some other units of the hospital were analysed. Nine electrophoretic types were found among the 31 strains (wild and ES beta las). The analysis of the results showed that 8 isolates of the group of 14 ES beta las had the same antibiotype and electrophoretic type. This demonstrates that one epidemic strain was responsible for two outbreaks, the first one in April and the second one in August-September. A case control investigation was carried out to define the risk factors of infection. Files were examined for the 14 infected inpatients and for 20 control inpatients from the same unit during the same period. Statistical analysis was performed with Epi Info software 5 (CDC Atlanta). Length of stay, dependence and malnutrition levels, and urinary sphincter disfunction were the most significant risk factors.
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Nouvellon M, Pons JL, Sirot D, Combe ML, Lemeland JF. Clonal outbreaks of extended-spectrum beta-lactamase-producing strains of Klebsiella pneumoniae demonstrated by antibiotic susceptibility testing, beta-lactamase typing, and multilocus enzyme electrophoresis. J Clin Microbiol 1994; 32:2625-7. [PMID: 7814515 PMCID: PMC264122 DOI: 10.1128/jcm.32.10.2625-2627.1994] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Nineteen extended-spectrum beta-lactamase (ESBla)-producing Klebsiella pneumoniae isolates from Rouen Hospital were investigated for their implication in nosocomial outbreaks: in addition to antibiotic susceptibility testing, the ESBlas were characterized by isoelectric focusing, and the genetic relationships between the strains were analyzed by multilocus enzyme electrophoresis using a combined polyacrylamide electrophoresis-electrophoretic transfer technique. Four isoelectric focusing beta-lactamase patterns and 11 enzyme electrophoretic types (ETs) among the strains tested were described. Three strains isolated in the same neurological unit over a 7-day period exhibited an SHV 3 beta-lactamase (pI 7.0) and were assigned to a common ET. Three of five strains isolated from patients in a rehabilitation center over a 6-week period harbored an SHV 4 beta-lactamase (pI 7.8) and exhibited the same ET. These results differentiate nosocomial transmission from sporadic cases and provide evidence that multilocus enzyme electrophoresis is a potential tool for studying genetic relationships between strains harboring a common ESBla.
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Pons JL, Combe ML, Leluan G. Multilocus enzyme typing of human and animal strains of Clostridium perfringens. FEMS Microbiol Lett 1994; 121:25-30. [PMID: 8082823 DOI: 10.1111/j.1574-6968.1994.tb07070.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Multilocus enzyme electrophoresis was developed to evaluate the genetic diversity of 71 human strains and 17 animal strains of Clostridium perfringens. Crude protein extracts, obtained by sonication of washed bacteria, were analyzed by polyacrylamide-agarose gel electrophoresis to characterize electrophoretic mobility variants of seven enzymes (esterase, glutamate dehydrogenase, glutamic-oxaloacetic transaminase, nucleoside phosphorylase, phosphoglucose isomerase, phosphoglucomutase, threonine dehydrogenase). Genetic diversity of the enzyme loci ranged from 0.340 to 0.813. Sixty-nine electrophoretic types were described among the 88 strains tested and the index of discrimination was 0.994. All strains were typable, and epidemiological relationships between isolates could be established. This method showed a fair correlation with esterase electrophoretic typing based on hydrolytic and electrophoretic polymorphism of esterases. This work demonstrates that multilocus enzyme polymorphism is a reliable and discriminant marker of genetic diversity of strains of C. perfringens.
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Pons JL, Picard B, Niel P, Leluan G, Goullet P. Esterase electrophoretic polymorphism of human and animal strains of Clostridium perfringens. Appl Environ Microbiol 1993; 59:496-501. [PMID: 8434914 PMCID: PMC202133 DOI: 10.1128/aem.59.2.496-501.1993] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Esterase electrophoretic polymorphism in human and animal strains of Clostridium perfringens was studied by using polyacrylamide-agarose gel electrophoresis. Five types of esterases, designated E-I to E-V and defined by their hydrolytic specificities toward five synthetic substrates, were found in protein extracts of bacteria grown without glucose (glucose-containing media allowed only the expression of esterase E-I). Mobility variants of esterase E-I, which hydrolyzes alpha- and beta-naphthyl acetates and butyrates, were used as a basis for the distribution of strains into 11 zymogroups. When all five types of esterases and their electrophoretic variants were considered, 77 electrophoretic types (ETs) could be described for the 89 strains tested. Animal strains did not constitute a distinctive subpopulation, as revealed by their distribution in the zymogroups and by clustering analysis. Statistical analysis also emphasized the importance of esterase E-IV (which hydrolyzes only naphthyl acetates) and esterase E-V (which hydrolyzes only alpha-naphthyl acetate) in clustering by the relatedness of the ETs. ETs allowed the epidemiological characterization of stool isolates recovered from elderly inpatient residents and from adolescent chronic-care psychiatric patients. These results indicate that esterase electrophoretic typing may be a marker for epidemiological and ecological analyses.
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Bories PN, Antoniotti C, Pons JL, Leluan G. Use of electrophoretic polymorphisms of esterases for differentiation of Clostridium argentinense strains. J Clin Microbiol 1993; 31:157-9. [PMID: 8417024 PMCID: PMC262643 DOI: 10.1128/jcm.31.1.157-159.1993] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Esterase electrophoresis was used to study 10 strains of Clostridium argentinense, including 7 toxigenic and 3 nontoxigenic strains. On the basis of the electrophoretic mobilities and hydrolytic specificities toward five synthetic substrates, different esterase profiles could be defined for almost all strains, revealing the heterogeneity of bacterial clones. Therefore, electrophoretic polymorphism of esterases can be used for differentiation of C. argentinense in population genetic or epidemiological studies.
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Pons JL, Bonnaveiro N, Chevalier J, Crémieux A. Evaluation of antimicrobial interactions between chlorhexidine, quaternary ammonium compounds, preservatives and excipients. THE JOURNAL OF APPLIED BACTERIOLOGY 1992; 73:395-400. [PMID: 1447055 DOI: 10.1111/j.1365-2672.1992.tb04994.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The antimicrobial interactions of 49 combinations of chlorhexidine, quaternary ammonium compounds, preservatives and excipients were evaluated by the method of Berenbaum and the checkerboard titration method, with Staphylococcus aureus CIP 53154 and Escherichia coli CIP 54127 as test strains. MIC determinations were carried out as a preliminary step, and relative growth intensity was used to describe the bacteriostatic activity of surface-active agents (Amonyl 380 BA, Amonyl 671 SB). In the study of combinations, results were interpreted with Fractional Inhibitory Concentration indexes and represented by isobolograms. A fair correlation was shown between the method of Berenbaum and the checkerboard titration method. Combinations between chlorhexidine, cetrimonium bromide and benzalkonium chloride were synergistic or additive; combinations of antiseptics and preservatives were generally not antagonistic. The methods were also well adapted to the study of interactions involving surface-active agents, a critical problem in the formulation of topical antimicrobial agents.
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Mazeron MC, Benjelloun B, Bertrand C, Pons JL, Pérol Y. Comparison of MRC-5 and continuous cell lines for detection of cytomegalovirus in centrifugation cultures. J Virol Methods 1992; 39:311-7. [PMID: 1331154 DOI: 10.1016/0166-0934(92)90104-l] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Continuous cell lines were assessed for use for rapid human cytomegalovirus (HCMV) detection procedures combining tissue culture, centrifugation, and immediate early antigen (IEA) immunostaining. Human cells (MRC-5 embryonic fibroblasts, U-373MG astrocytoma cells, differentiated teratocarcinoma (Tera-2) cells), murine cells (BALB/c-3T3 and Y-1 cells), BHK21 hamster cells, and mink lung (ML) cells were first inoculated with HCMV laboratory strain. IEA synthesizing cells were detected by immunoperoxidase assay using a monoclonal antibody. ML cells and differentiated Tera-2 cells exhibited more positive cells than MRC-5 cells. BHK21, and MRC-5 cells were equivalent in sensitivity whereas U-373MG, BALB/c-3T3, and Y-1 cells had only reduced IEA positive cells. When 63 urine specimens were inoculated onto MRC-5, ML and differentiated Tera-2 cells, 20 (31.7%) were positive in MRC-5 cells versus 18 (28.5%) in ML or Tera-2 cells. Moreover, greater numbers of infected cells were detected in MRC-5 cells than in these two cell lines. MRC-5 cells were superior for detection of HCMV in clinical samples by centrifugation cultures.
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Crémieux A, Reverdy ME, Pons JL, Savage C, Chevalier J, Fleurette J, Mossé M. Standardized method for evaluation of hand disinfection by surgical scrub formulations. Appl Environ Microbiol 1989; 55:2944-8. [PMID: 2696429 PMCID: PMC203195 DOI: 10.1128/aem.55.11.2944-2948.1989] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A standardized protocol for the evaluation of hand disinfection by surgical scrub formulations was applied to volunteers in a multicenter trial. Povidone iodine (PVI), chlorhexidine (CHX), and a nonmedicated soap (NMS) were tested. The scrubbing procedure involved three daily hand washings for five consecutive days; surviving bacteria were counted daily after being collected in a suitable neutralizing solution. Immediate efficacy (IE), cumulative efficacy (CE), and remanent effect (RE) were calculated by reference to the control hand. Statistical analyses of IE, CE, and RE showed significant differences among the three scrub formulations. IEs of PVI and CHX were equivalent and different from IE of NMS; CE and RE of CHX were higher than those of PVI and NMS. On the basis of the statistical analysis, the population size required for further studies aimed at detecting significant differences between surgical scrub formulations could be estimated.
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Pons JL, Rimbault A, Darbord JC, Leluan G. Gas chromatographic-mass spectrometric analysis of volatile amines produced by several strains of Clostridium. JOURNAL OF CHROMATOGRAPHY 1985; 337:213-21. [PMID: 3988853 DOI: 10.1016/0378-4347(85)80034-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A gas chromatographic--mass spectrometric technique is proposed for the analysis of volatile amines which were isolated from Clostridium cultures by vacuum distillation and concentrated as hydrochloride salts. Headspace sampling after alkalinization of the salts under vacuum was the most suitable for subsequent gas chromatographic analysis. With ammonia-loaded helium as carrier gas, methylamines were separated on 4.8% PEG 2OM + 0.3% potassium hydroxide on Carbopack B, and other volatile amines on 28% Pennwalt 223 + 4% potassium hydroxide on Gas-Chrom R. Bacterial volatile amines (dimethylamine, trimethylamine, isobutylamine, 3-methylbutylamine, etc.) were detected with a flame-ionization detector and identified by gas chromatography--mass spectrometry in electron-impact and chemical ionization modes.
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Pons JL, Rimbault A, Darbord JC, Leluan G. [Biosynthesis of toluene in Clostridium aerofoetidum strain WS]. ANNALES DE MICROBIOLOGIE 1984; 135B:219-222. [PMID: 6508079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Formation of toluene in growing cultures of Clostridium aerofoetidum strain WS was enhanced when the medium was supplemented with phenylacetic acid or with L-phenylalanine and L-methionine together. Evidence for the role of L-phenylalanine was shown by the detection of [2H2]-methyl[2,3,4,5,6-2H5]benzene ("heptadeuterotoluene") in growing cultures with L-[2',3',4',5',6'-2H5]phenyl[2,3-2H3]alanine and L-methionine.
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Peloux Y, Desideri D, Pons JL. [Food poisoning caused by Vibrio parahaemolyticus]. LA NOUVELLE PRESSE MEDICALE 1981; 10:3074-5. [PMID: 7290969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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