PubMed Health⌕ Search

Biomedical subjects

J Paysant

Publications and source records attributed to J Paysant.

At least 19 recordsLinked to original sources
PubMed2003

Cooperation between monocytes and breast cancer cells promotes factors involved in cancer aggressiveness.

In breast cancers, clinical symptoms of inflammation localised around the tumour at the time of diagnosis have been considered to have poor prognosis significance. In this study, the biological mechanisms responsible for the deleterious action of monocytes in cancer were investigated. The incubation of the breast-cancer-derived MDA-MB231 cells with monocytes resulted in an increase in factors involved in cell invasion (i.e. both cancer cells and monocytes-associated urokinase and Tissue Factor, and PAI-1 and MMP-9 secretion). Moreover, the functions of monocytes were also modified. Incubation of monocytes with MDA-MB231 cancer cells resulted in a downregulation in the secretion of the antiproliferative cytokine Oncostatin M, while the apoptotic factor TNF alpha was dramatically increased. However, MDA-MB231 cancer cells have been shown to be resistant towards the apoptotic action of TNF alpha. These findings demonstrate that incubation of MDA-MB231 cancer cells with monocytes induced a crosstalk, which resulted in an increased expression of factors involved in cancer cell invasiveness and in a modification of monocytes function against cancer cells, while inflammatory effects were increased.

Breast Neoplasms↗
PubMed2003

[Comparative study of effort training in deconditioned patients with and without pain. A preliminary study].

INTRODUCTION: The deconditioning or disuse syndrome is a recent nosological entity, based on medical, professional, social and psychological arguments. The aim of the study was to measure the physical condition in deconditioning situation and to evaluate the effectivity of a training program on five chronic painful patients and five painless subjects. METHODS: After determining the physical aspects of the deconditioning syndrome using three tests and evaluating pain, this prospective study evaluated the benefits of a six weeks effort training period called "interval training" in subjects with and without chronic pain. The inclusion criteria were the patient's consent, the absence of etiological treatment of the pain and the absence cardiotropic medication. The data were compared using the t-test of Student. After the training protocol, people were satisfied. A significant increase of Maximum Oxygen Uptake, Maximum Tolerance Power duration of recovery and cardiac adaptation of effort were observed. Pain didn't seem to be a limited factor to cardiac effort training and decreased actively after the program. CONCLUSION: A training effort protocol can help to reduce the deconditioning syndrome whether people are painful or not. The improvements of physical parameters seem to be reinforced by a better self assurance.

Adult↗
PubMed2003

The effect of inturning of the foot on knee kinematics and kinetics in children with treated idiopathic clubfoot.

OBJECTIVE: To assess the effect of internal foot progression angle (inturning) on knee dynamics in children with treated clubfeet. DESIGN: Prospective study dividing a population of clubfeet according to the factor inturning. BACKGROUND: Excessive internal or external foot progression angle increases knee flexion by a backward shift of the ground reaction force to the knee joint in children with cerebral palsy. Similarly, inturning in clubfeet was hypothesized to shift the ground reaction force backwards with reference to the knee joint, increasing the external knee flexion moment and the maximal knee flexion at stance. METHODS: Three-dimensional gait analysis was performed on 20 children with surgically treated clubfeet (n=28) to assess alterations of knee dynamics related to inturning (>7 degrees ) and on 13 normal children. RESULTS: Inturning occurred in 46% of the clubfeet and was associated during stance, at maximal knee flexion, to an increase in maximal knee flexion (+7 degrees ), external knee flexion moment (+60%) and related lever arm to the knee (+100%) and at minimal knee flexion, to a reduction in external knee extension moment (-62%) and related lever arm (-58%). Inturning was associated with a more frequent prolongation of internal knee extension moment and of rectus femoris activity exceeding 50% of stance. CONCLUSION: Inturning in clubfeet is associated with knee dynamics alteration, which might contribute to the long-term development of knee osteoarthritis. RELEVANCE: The therapeutic correction of inturning in clubfeet would be of importance if the consecutive knee dynamics alteration is shown by further studies to contribute to long-term degenerative knee pathology.

Adolescent↗
PubMed2003

[Disorders of the processing of spatial information in patients with right cerebral lesions and left hemi-neglect].

The aim of this research was to identify, analyze and classify disorders in behavior which occur in the use of mirrors in patients with right cerebral damage presenting left visual spatial hemiplegia. This work was based on models of visual information processing. Seven controls and eleven patients with right cerebral damage performed a test involving grasping of an object using only specular information from a conventional mirror and then from an inverted mirror. The controls grasped up all the cubes straight away. They only experienced minor difficulty with the inverted mirror, mainly in relation to lateral displacement. The patients revealed a variety of behaviors: 1) searching for and trying to seize the object in the conventional and/or inverted mirror, 2) inversion of the paralysed side (left versus right) in the inverted mirror or the appearance of a visual spatial hemiplegia, 3) modifications in the order of grasped (from right to left, from left to right, or at random), 4) directional anomalies in the horizontal plane linked (or not) with disorders in the use of the anteroposterior space. The results of this study confirm that the patients have abnormal behavior in mirror spaces. While the characteristics of this behavior shows analogies with those described in the non-recognition of objects and/or defects in the processing of visual information for localising objects in space, they can be disassociated from them, and constitute separate syndromes. Specific terminology and taxonomy for the clinical forms of mirror agnosia and specular agnosia, of mirror paralysis and specular paralysis, and of specular ataxia are proposed.

Adult↗
PubMed2002

Functional asymmetries of the lower limbs. A comparison between clinical assessment of laterality, isokinetic evaluation and electrogoniometric monitoring of knees during walking.

We used bilateral electrogoniometric gait monitoring of the knees to demonstrate the existence of an angular asymmetry between the two legs in healthy subjects. We also searched for correlations between this asymmetry and handedness, footedness and ocular laterality and isokinetic strength of the flexor-extensor muscles of the two knees. Among the 40 subjects studied, 25 (62.5%) showed an asymmetric maximal knee flexion: the difference being superior or equal to 5 degrees between the knees. There was no correlation between this asymmetry and the lateralities studied. We termed this type of asymmetry 'angular preponderance' to differentiate it from the laterality defined by clinical tests. Isokinetic strength of the knee flexors and extensors was correlated with the gender and speed, but not with side or laterality. Appropriate interpretation of lower limb examination should take into consideration angular gait asymmetry in the healthy subject.

Adult↗
PubMed2001

Decrease of breast cancer cell invasiveness by sodium phenylacetate (NaPa) is associated with an increased expression of adhesive molecules.

Sodium phenylacetate (NaPa), a non-toxic phenylalanine metabolite, has been shown to induce in vivo and in vitro cytostatic and antiproliferative effects on various cell types. In this work, we analysed the effect of NaPa on the invasiveness of breast cancer cell (MDA-MB-231, MCF-7 and MCF-7 ras). Using the highly invasive breast cancer cell line MDA-MB-231, we demonstrated that an 18-hour incubation with NaPa strongly inhibits the cell invasiveness through Matrigel (86% inhibition at 20 mM of NaPa). As cell invasiveness is greatly influenced by the expression of urokinase (u-PA) and its cell surface receptor (u-PAR) as well as the secretion of matrix metalloproteinases (MMP), we tested the effect of NaPa on these parameters. An 18-hour incubation with NaPa did not modify u-PA expression, either on MDA-MB-231 or on MCF-7 and MCF-7 ras cell lines, and induced a small u-PA decrease after 3 days of treatment of MDA-MB-321 with NaPa. In contrast, an 18 h incubation of MDA-MB-231 increased the expression of u-PAR and the secretion of MMP-9. As u-PAR is a ligand for vitronectin, a composant of the extracellular matrix, these data could explain the increased adhesion of MDA-MB-231 to vitronectin, while cell adhesivity of MCF-7 and MCF-7 ras was unmodified by NaPa treatment. NaPa induced also an increased expression of both Lymphocyte Function-Associated-1 (LFA-1) and Intercellular Adhesion Molecule-1 (ICAM-1), which was obvious from 18 hour incubation with NaPa for the MDA-MB-231 cells, but was delayed (3 days) for MCF-7 and MCF-7 ras. Only neutralizing antibodies against LFA-1 reversed the decreased invasiveness of NaPa-treated cells. Therefore we can conclude that the strong inhibition of MDA-MB-231 invasiveness is not due to a decrease in proteases involved in cell migration (u-PA and MMP) but could be related both to the modification of cell structure and an increased expression of adhesion molecules such as u-PAR and LFA-1.

Antineoplastic Agents↗
PubMed2001

Mirror images and unilateral spatial neglect.

Responding correctly to a mirror image requires the creation of a rather peculiar form of dual representation. Mirror agnosia and mirror ataxia, i.e. a deficit in reaching an object reflected in a mirror, have been reported to be associated with parietal lobe lesions. This prospective study was conducted to investigate the capacity of subjects with neglect to identify the mirror image nature of visual information. Four consecutive brain-damaged patients with neglect, selected on the basis of specific criteria, and four control subjects performed grasping and object displacement tests under two response conditions (normal mirror and inverted mirror). Video recordings of the tests were analyzed to assess performance using the following criteria: (i) direction of the arm movement during the initial phase of movement, (ii) number of corrections of the hand position before grasping. The control subjects successfully grasped the objects in both experimental conditions. The patients (1) neglected the contralesional space, grasping objects correctly in the ipsilesional space (normal mirror condition) and (2) neglected the ipsilesional space, grasping correctly objects in the contralesional space (inverted mirror). Controls used real object-centered correction clues to modify the position and direction of their hand movement. The patients only produced horizontal displacements of the upper limb in the "healthy" and neglected space. These results suggest that patients with neglect do not use the same clues and do not modify their procedures as they cannot recalibrate their spatial representations. These differences concerned non-mirror-image clues and directional and positional as well as attentional vectors. Theoretical and rehabilitative implications are discussed.

Adult↗
PubMed2001

[Classification and mechanisms of body perceptions in the amputees].

OBJECTIVE: Amputees can experience several types of physical illusions and phantom limb phenomenon. The objective was to establish a synthetic classification of theses perceptions. METHOD: Prospective study in 75 amputees (group 1: amputation (n = 60), group 2: congenital defect). The subjects were asked first to report their perceptions spontaneously and then to detail the perception, if exist, of the missing limb: form recognition, posture, movement, reminiscence of a lost limb. RESULTS: Different types of perception were described besides the perception of the real state : normal, deformed or commemorative phantom limb and illusion of a normal body. DISCUSSION: Whatever the model (i.e.: neuro-matrix) which support the construction of the scheme and the body image, the representations related to identified perceptions, use various innate, autobiographic and identity frames of references as well as instantaneous peripheral information, treated by reorganized cerebral structures. Each type of perception is related to a particular representation pattern. CONCLUSION: This approach, in accordance with the literature, offers a better understanding of the differences between amelic and amputated subjects and of their perception of any prosthetic equipment.

Amputees↗
PubMed2001

[MRI and leg stump neuroma].

OBJECTIVE: To describe RMI aspects of leg stump neuroma and to evaluate RMI scan interest for neuroma diagnosis and management. POPULATION AND METHOD: During a 2 years period, 224 amputated patients consulting for pain or prostetics problems were studied. In 10 cases, a characteristic pain leads to neurona diagnosis. This is described as a sensation of ascending or descending electric shock induced by the stimulation of an identified point with a reproducible topography. In all these cases, RMI scans were performed. In thirty two other cases, a RMI scan was performed to confirm a pathology (bursitis, bone abnormality) or in order to establish an etiologic diagnosis. Twelve neuromas were diagnosed. RESULTS: RMI scan showed a neuroma in the ten cases with a clinical suspicion and two asymptomatic neuromas were diagnosed out of the 32 patients without clinical suspicion. Medium delay between amputation and neuroma diagnosis is 11,6 year. In six cases, staking was modified and in six other cases, surgery was necessary. In aIl cases, clinical manifestations disappeared. Vanous RMI aspects ofneuromas are described and illustrated. Neuroma is observed on the extremity of a nerve that have a wavy aspect on its top. The neuroma is an oblong structure, with clear limits. There is an hyposignal with Ti sequence and variable signal with T2 and after gadolinium injection. DISCUSSION: RMI scan is a good way to diagnose amputee neuroma. It makes it possible to demonstrate the pathological character of the neuroma. It has to be performed when a neuroma is suspected. It enables to confirm the diagnosis and establish the exact topography and anatomic connection. Mechanical strains role as a factor of discovering the neuroma is discussed because of the concomitant evolution of associated lesions (bursitis, bone edema). Surgical repair takes place after correcting abnormal mechanical strains.

Amputation, Surgical↗
PubMed2001

[Rehabilitation protocols after repairs of zone 2 of the flexor tendon of the hand: presentation and indications].

We report the results of a retrospective study of 47 adult patients corresponding to 54 fingers, operated on in the emergency room at Nancy University Hospital between December 1996 and October 1998. These patients were managed using three different postoperative therapy protocols: passive mobilisation according to the Duran technique, active-passive mobilisation according to the Kleinert technique and immediate active mobilisation as described by Strickland. Patients were evaluated in three different ways; active range of movement obtained according to the Strickland scale, the "400 points" flexor function test and the delay in returning to work. Combining all three evaluations showed a 65% rate of satisfactory results, 22% fair and bad results and 13% ruptures. Analysis according to the re-education technique showed a strong superiority of the Strickland protocol. This now needs to be confirmed by a more extensive prospective study. Delay before return to work is not affected by the type or re-education technique chosen, but side-effects are less frequent with the Strickland method. A result in terms of range of active movement alone did not fully evaluate the result of a flexor tendon repair: functional testing was better at this end and the global "400" points test score gave more useful information than each of its component tests taken individually (Purdue pegboard, Minnesota test, Box and Block). Functional testing seemed more helpful in guiding the medical team in its treatment strategy.

Adult↗
PubMed2001

Vestibular caloric stimulation evokes phantom limb illusions in patients with paraplegia.

STUDY DESIGN: Prospective study. OBJECTIVES: To determine the mechanisms of body illusions in paraplegia patients as compared with the amputee phantom phenomena. METHODS: A vestibular caloric stimulation was performed in 10 consecutive patients with complete section of the spinal cord. Perception of body, before and after stimulation, was classed as illusion of a normal body (lower limbs with normal morphological, postural and kinetic characteristics perceived as before spinal injury), normal phantom (overly vivid perception of all or part of the lower limbs), deformed phantom (perception of all or part of the limbs below the injury level as abnormal in shape, posture, movement or even number), or painful phantom. RESULTS: After vestibular caloric stimulation, nine out of 10 patients stated their perception of body segments below the injury level had changed to normal phantoms or to deformed phantoms (morphological, postural or kinetic changes). Among the four patients who initially had painful limbs, two stated the stimulation greatly relieved their pain. CONCLUSION: The normal or deformed phantom evoked by vestibular stimulation would result from use of identity data or instantaneous data as is observed in amputees. Cerebral remapping following deafferentation could be the origin of the deformed phantoms. Illusions corresponding to phenomena perceived at the time of the accident corresponding to autobiographical engrammes do not appear to be evoked by vestibular stimulation, as is also the case in amputees.

Adult↗
PubMed2001

Comparison of the contractile responses of human coronary bypass grafts and monkey arteries to human urotensin-II.

Human urotensin-II (hU-II) is a cyclic peptide recently cloned in humans and present in human cardiac tissue and human arteries. The effects of hU-II were studied on human coronary bypass grafts in vitro. In three out of eight human mammary arteries, and two out of three human radial arteries, hU-II caused contraction; human saphenous veins did not respond to hU-II. When it exists, the contraction slowly develops and has a low-to-moderate intensity. All radial arteries obtained from young healthy non-human primates contracted strongly to hU-II.

Aged↗
PubMed2001

[Georges Gilles of Tourette, pioneer of gait analysis in the nervous system diseases].

Georges Gilles de la Tourette's contribution to neurology goes beyond the description of the neurological disorder named after him. On December 28, 1885, he defended his doctoral thesis devoted to "gait in the diseases of the nervous system, studied by the method of imprints". In collaboration with Albert Londe, he worked for two years in Charcot's department on "a simple method applicable to both healthy and unhealthy patients", establishing the scientific and modern basis of functional exploration of human gait. The purpose was to "record the modifications of the gait and to fix them permanently, using suitable devises to guarantee not only rigorous comparison, but also to prevent observers, making use of the same method, from disputing or canceling the results completely independent of the experimenter himself". Georges Gilles de la Tourette defined the various characteristic parameters and provided the normal reference values in males and females, determining the physiological asymmetry of steps. He described spastic gait, shaking palsy, and locomotor ataxia. He distinguished between disorders of nervous control and related joint diseases. He also classified gait disorders occurring during hemiplegia. Modern development of kinetic, kinematic and biomechanical studies is a good illustration of the current relevancy of Gilles de la Tourette's contribution.

France↗
PubMed2001

[Illusions of body normality in amputees and paraplegic patients].

Phantom limbs in amputees, or body illusion in hemiplegics, have been the subject of wide ranging descriptions. The detected abnormalities involve morphological, postural and/or kinetic features. The aim of this prospective study carried out in 25 amputees and 10 adult paraplegics was to describe the typology of these perceptions. Data were collected from free and semi-directive investigations before and after caloric vestibular stimulation. Amputees and paraplegics perceived normal, deformed and painful body phantom segments, reffered perceptions and "normal limbs" which took on the request posture considering the general body position (illusion of body normality). This perception corresponds to an image of the body, such as it should be and not such as it is. In amputees, the limb follows the movements of the prothesis. These perceptions conform quite well reality so that the loss of the paralyzed limb is not perceived as a missing limb. This illusion of body normality should be distinguished from the normal phantom limb, characterized by a stronger perception of the lost limb compared with the other. In both amputees and paraplegics, vestibular stimulation can generate or modify phantoms limbs or body illusion and can abolish painful phantom limbs. The neuromatrix, which rebuilds body representations, could get its information from reorganized cortical areas (instantaneous body image), autobiographical engrams (painful phantoms limbs), or innate engrams (identity body schema) that, via congruence mechanisms, could be identified as a somatic reference, particularly for motor programming. This interpretation is compatible with current knowledge and suggests how amputees can easily use a prothesis.

Adult↗
PubMed2000

Buccal hemineglect.

OBJECTIVES: To determine whether the peripersonal and intrapersonal buccal space can be affected by a hemispheric stroke and to evaluate the clinical signs resulting from buccal neglect. METHODS: A prospective study comparing 2 groups of patients with hemiplegia, 1 with a right hemispheric lesion and the other with a left hemispheric lesion. Patients were selected consecutively on the basis of specific criteria at least 1 month after stroke. RESULTS: Buccal hemineglect was usually concomitant with other hemineglect phenomena resulting from lesions of the right hemisphere (10 of 12 in right lesions and 1 of 12 in left lesions). Clinical signs associated with this condition consisted of impaired swallowing (retention, defective insalivation, presence of food debris in the left hemibuccal space, loss of saliva from the left side of the mouth, and choking); loss of the ability to perceive salty, sweet, or acid tastes; and impaired buccal representation. These problems were usually incorrectly diagnosed initially. Outcome was usually favorable, but functional disorders persisted in some patients for more than 18 months. The underlying attention and representation mechanisms are discussed with reference to experimental lesions of the postarcuate (area 6) cortex in rhesus monkeys. The area around the mouth may be considered to be, as in monkeys, a peripersonal space, ie, probably of little functional importance. The lesion may involve area 6 or its projections to the thalamus or posterior parietal cortex. CONCLUSIONS: Buccal hemineglect, which is likely to cause social embarrassment, should be considered whenever the oral phase of swallowing is impaired in a context of neglect syndromes. Prophylactic measures and rehabilitation can reduce the impact and complications of the condition (food bolus).

Adult↗
PubMed2000

Factors influencing the effect of the soluble IL-6 receptor on IL-6 responses in HepG2 hepatocytes.

The soluble IL-6 receptor (sIL-6R) can increase IL-6-induced signalling by forming a complex with IL-6 and membrane-bound gp130 (the receptor beta chain which transduces signals). The conditions affecting this response to sIL-6R were studied using fibrinogen release from HepG2 hepatocytes. Exogenous sIL-6R had no effect alone or in the presence of a submaximal concentration of IL-6, but increased responses to supramaximal IL-6 concentrations in a concentration-related manner. Dexamethasone increased the expression of the membrane IL-6R and endogenous sIL6R release, and increased responses to supramaximal but not submaximal IL-6 concentrations. The amount of endogenous sIL-6R released is relatively small and is unlikely to influence the effects of the exogenous sIL-6R. The observed concentration-related decrease in sIL-6R production in the presence of IL-6 may indicate internalization of ligand/receptor complexes. This would significantly decrease the amount of IL-6R (soluble or membrane) available for signalling and limit continued functional response later in the cultures. These data indicate that the major factor influencing responses to exogenous sIL-6R is an excess of IL-6 which is necessary to form complexes with the sIL-6R, which can then interact with gp130 to increase signalling.

Carcinoma, Hepatocellular↗
PubMed2000

Imaging of the painful lower limb stump.

Several postoperative complications associated with pain may develop in the stump of an amputated lower limb. Clinical findings are often nonspecific; however, radiologic evaluation, especially with magnetic resonance (MR) imaging, is useful in the early diagnosis of these complications, thereby helping minimize physical disability with its psychologic and socioeconomic implications. Conventional radiography can demonstrate evidence of osseous origins of pain (eg, aggressive bone edge, heterotopic ossification, osteomyelitis) and should be the first imaging study performed after clinical examination. Videofluoroscopy can help evaluate improper prosthetic fit by demonstrating abnormal residual limb motion, piston action, rolling of soft tissues, and abnormal angle between the limb axis and the prosthesis during gait. Ultrasonography can demonstrate inflammatory changes in the stump as well as soft-tissue fluid collections. However, MR imaging is the modality of choice when clinical and other imaging findings are indeterminate. Because of its high spatial and contrast resolution, MR imaging can demonstrate subtle inflammatory changes, fluid collections, cancers, neuromas, and subtle traumatic bone lesions. Knowledge of various surgical and rehabilitation techniques is required for accurate diagnosis of complications associated with stump pain. Correct diagnosis allows choice of the most appropriate therapy, which may involve treating the stump, remodeling the prosthesis, or both.

Amputation Stumps↗