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J Michon

Publications and source records attributed to J Michon.

At least 127 records · Page 7Linked to original sources
PubMed1989

[Anatomic variations of the vascular network of the first dorsal commissure. Uses of the kite flap].

Thirty dissections were performed on fresh, unfixed, adult cadavers after vascular injection of silastic or methylene blue. Analysis of the results led to replacement of the concept of a single dorsal intermetacarpal artery, the constant pedicle of the kite flap, by that of an intermetacarpal vascular system composed of one or two supra- and/or sub-aponeurotic vessels. The existence of distinct direct skin branches of this intermetacarpal vascular system is defined. The various possible modes of vascularisation of the kite flap are listed, defining the situations at risk and leading to precise practical applications in terms of surgical technique.

Adult↗
PubMed1989

[A single-use vascular clamp. An experimental and clinical study].

Twelve rabbit femoral arteries were clamped for one hour with a TKS2 clamp in order to confirm the atraumatic nature of the Tamai disposable clamp. After 15 or 30 minutes of revascularisation, the arteries were excised and studied by light microscopy and scanning electron microscopy. Temporary dilatation of the artery was observed after removal of the clamp, as the patency test was always positive. Light microscopy revealed parietal flattening without any cellular disorganisation and scanning electron microscopy revealed flattening of the endothelial cells without any tearing. On the basis of these favourable results, combined with the ease of use, we now use the Tamai clamp daily.

Animals↗
PubMed1989

[Effect of ornithine oxoglutarate on the duration and quality of wound healing in extensive reparative and plastic surgical methods].

Fifty-two overweight female patients hospitalized for a major plastic surgical procedure were included in a therapeutic trial designed to evaluate wound healing. Twenty-seven patients were randomized to a placebo and 25 to ornithine oxoglutarate (Cetornan). There were no statistical differences between patients concerning age, type of plasty, extent of detachment, or overall evaluation of physical condition at the time of randomisation. Evaluation was based mainly on clinical criteria, including duration and quality of healing, and type of complications. Results showed a significant improvement in time to healing in the Cetornan group (18 +/- 1 day) as compared to the placebo group (26 +/- 3 days) (p less than 0.01). Complications occurred in nine of the 27 patients under placebo (30%) and in three of the 25 patients under Cetornan (12%) (p = 0.07). Clinical and biological tolerance was outstanding. No patient was excluded during the trial.

Adult↗
PubMed1989

[Limitations of replacing the semilunar with a Swanson's implant].

Nineteen patients have had an arthroplasty of the semilunar by Swanson's prosthesis at stage III of Kienbock's disease. They have been reviewed after an average period of 4 years. The clinical evaluation finds 14 good and excellent results, two fair and 3 poor ones. Its analysis shows a persistence of a non limiting pain 15 times; a fair muscular strength which reaches 65 per cent of the strength of the healthy side and articular amplitudes reduced by 36 per cent of the normal amplitude. Radiologically, the study of the wrist as a whole shows that the prosthetic implantation avoids the aggravation of the collapse of the wrist, whereas its cubital sliding increases by about 15 per cent. The analysis of the evolutive mode of the wrist shows a subluxation of the scaphoid which leads 15 times to a scaphoradial arthrosis; 17 times were observed lytic signs which in 4 cases have evoked a synovitis. It seems therefore that the clinical results are favourable more than 3 times out of 4, but radiological signs of osteoarticular degeneration show the necessity to stabilize the external column of the wrist, in order to avoid the deterioration of the Swanson's implants.

Adolescent↗
PubMed1989

[Role of orthosis in the treatment of stiffness of the hand].

The statistical analysis of results obtained with splinting treatment of finger and hand stiffness, and derived from a series of 635 motion range measurements taken on 249 hand joints, provided us with sufficient data to identify the various factors likely to have an impact on the therapeutic outcome. A mean increase of 25.8% in the range of movements is enough to justify the use of orthosis, although this figure actually varies substantially with the patient's age, the duration of the stiffness, the latter's degree and origin, the joint involved, and the duration of the orthotic treatment. An analysis of the time factor enabled us to establish the date beyond which changes for recovery are quite limited, whereby allowing to schedule surgical mobilization.

Hand Deformities↗
PubMed1988

T11/CD2 activation of cloned human natural killer cells results in increased conjugate formation and exocytosis of cytolytic granules.

The T11 (CD2) antigen has been found to be an alternate pathway for antigen-independent activation of resting T cells. T11 triggering also results in activation of NK cells and enhancement of their cytolytic function. The present studies were carried out to further define the mechanisms whereby cytotoxicity is enhanced after T11 activation. A series of clonal human NK cell lines were analyzed after incubation with monoclonal anti-T112 and anti-T113 antibodies specific for different epitopes of the CD2 protein. Anti-T112/3 triggering resulted in increased cytotoxicity against a variety of target cells. Similar results were obtained with F(ab')2 fragments of anti-T112/3, indicating that this effect was not mediated through binding of FcR. The induction of cytotoxicity was found to be associated with increased formation of effector cell-target cell conjugates and with release of secretory granule-localized 35S-labeled proteoglycans. Both enhanced conjugate formation and cytotoxicity could be blocked by anti-lymphocyte function-associated antigen (LFA-1) mAb. Ultrastructural analysis of NK cells after T11 activation demonstrated increased adherence of effector cells to targets and other NK cells as well as a directional reorientation of cytoplasm and intracellular granules toward the area of contact between cells. Discharge of granules occurred into pockets bounded by closely apposed plasma membranes. In the presence of anti-LFA-1 and anti-T112/3, the close apposition and formation of pockets between effector cells and target cells did not occur but the cells exocytosed their intracellular granules. T11 activation of NK cloned cells also resulted in the formation of the homotypic conjugates and autocytotoxicity. As seen with resistant allogeneic targets, autocytotoxicity was mediated by F(ab')2 fragments of T112/3 antibodies and could be blocked by anti-LFA-1 antibody. Ultrastructural analysis of NK cloned cells after T11 activation confirmed the presence of homotypic conjugates with reorientation of effector cells toward one another and discharge of cytolytic granules into pockets formed between NK cloned cells. Taken together, these results indicate that T11-induced cytolytic function of NK cells is, in part, mediated through increased binding of effector cells and targets and that enhanced conjugate formation is at least in part mediated by the LFA-1 antigen. In addition, T11 activation results in the triggering of the cytolytic mechanism of NK cells and the exocytosis of cytolytic granules and their constituents.

Antibodies, Monoclonal↗
PubMed1988

Characterization of functional surface structures on human natural killer cells.

Recent studies on human NK cells have identified a number of surface antigens that can be utilized to define this population of cells and to identify functionally distinct subsets within this heterogeneous population. In addition, it has been possible to associate specific functional activities with several antigens expressed on NK cells as well as other hematopoietic cells. This information, which is summarized in Table III can be utilized to develop a framework for the classification of cytolytic effector cells. Of primary importance, this classification identifies subsets of cytolytic cells with distinct functional repertoires and distinct cytolytic mechanisms. The majority of NK cells in unstimulated peripheral blood and the majority of NK clones express NKH1 and CD2 antigens but do not express CD3 antigen. These cells morphologically appear as large granular lymphocytes and have broad cytolytic activity against a variety of allogeneic targets without primary sensitization. Consistent with the finding that these cells are CD3 negative, they have not been found to have rearrangement of genes encoding for TCR, or functional mRNA transcripts of either TCR alpha, TCR beta, or TCR gamma genes. In addition, these cells do not express heterodimeric surface proteins similar to those that have now been demonstrated to be MHC-restricted T cell receptors for antigen. Taken together, these findings provide strong evidence that NKH1+CD3- NK clones do not interact with target cells through a T cell receptor-like structure. Nevertheless, these NK cells do share several properties with conventional CTL. These functional T cell characteristics include (1) expression of CD2-T11/E rosette receptor antigen, and (2) utilization of LFA-1 surface antigen to enhance effector cell adhesion to target cells. As previously demonstrated for T cells, NK cells can be activated through the CD2 molecule and this has recently been shown to result in the enhancement of cytolytic function by these effectors. Since CD2 can also function as a cell surface ligand for LFA-3, an antigen expressed on NK targets, the CD2 molecule may be considered as a potential NK receptor structure. The fact that a very small subset of NK cells (approximately equal to 10%) as well as some NK clones (JT11) does not express CD2 argues against a potential role for CD2 as the NK cell receptor. Certainly, further studies will be necessary to clarify the role of CD2 on NK cells and to identify the mechanisms whereby NKH1+CD3- NK cells interact with targets in a non-MHC-restricted fashion.(ABSTRACT TRUNCATED AT 400 WORDS)

Antibodies, Monoclonal↗
PubMed1988

Hyperostotic macrodactyly.

There is a rare and special type of macrodactyly that is called the hyperostotic variety. This disease occurs later than the classical forms of macrodactyly and shows massive osteocartilaginous deposits around the joints. A new case is reported. The cause of this disease could be previous trauma.

Adult↗
PubMed1988

[Miniaturized osteosynthesis of articular fractures of the fingers. Results of a series of 60 cases].

The importance of anatomical reduction of articular fractures and early mobilisation of these severe forms of trauma which frequently damage the extensor apparatus (58% of cases, led us to propose direct miniaturised osteosynthesis as described by the Nancy-Strasbourg team. Of the 1,000 cases of osteosynthesis performed between 1978 and 1985, we selected 12 fractures of the MP joint, 38 fractures of the PIP joint and 10 fractures of the DIP joint, differentiated into 4 stages according to the condition of the skin and tendons and into 9 categories according to the anatomical type and the site of the fracture. Direct osteosynthesis (screw, bolt, pin) was used in every case. The clinical results were evaluated in terms of the Total Active Range of Movements, the local trophic state, the amount of pain and return to work, for each joint. When well conducted and with effective skin cover, this technique allows almost normal reconstruction in simple fractures and is valuable in more complex fractures by preserving sliding of the tendinous apparatus due to early mobilisation.

Adolescent↗
PubMed1988

Use of glutaraldehyde stabilized mammalian pericardium in hand surgery.

Initial feasibility studies of glutaraldehyde-stabilized bovine pericardium show promise for use in hand surgery. The pericardium exhibits excellent handling characteristics with no obvious biologically adverse reactions. Testing in the experimental models show a decrease in adhesion formation and an increase in tendon gliding. Clinical use of the bovine pericardium in selected cases appears to be confirm the experimental results.

Animals↗
PubMed1987

Molecular localization to a unique DR beta-chain of the restriction element of an anti-influenza T cell clone.

The DR beta-chains of a panel of DRw13 cells were characterized by two-dimensional polyacrylamide gel electrophoresis in order to identify the molecule bearing the restriction element of a DR-restricted proliferative and cytotoxic T cell clone COT C2 specific for DRw13 and the influenza A virus. Because in different DRw13 haplotypes one DRw13 beta-chain can be associated with other distinct DRw13 beta-chains, such complex associations allowed us to determine the ability of a given DR beta-chain to present the antigen or COT C2. The presence of the DR beta-chain 6B5, and only this chain, is associated with the ability to induce the proliferation of clone COT C2 whatever the second DR beta-chain associated with 6B5 is, namely 6B4 or 6B3. The DRw13 cells that express 6B4 or 6B3 but not 6B5 could not present the antigen to COT C2. Moreover, ILR2, a monoclonal antibody that precipitated 6B5, blocked the proliferation of COT C2, whereas 7.3.19.1, a monoclonal antibody that precipitated only 6B4 and 6B3, could not block the proliferation of this clone. Thus, the DRw13 beta-chain 6B5 appears as the unique class II element that restricts the response of the T cell clone COT C2.

Antibodies, Monoclonal↗
PubMed1987

Autoreactive T cell clones of MHC class II specificities are produced during responses against foreign antigens in man.

Although the existence of autoreactive T cells has been widely reported in mice and in guinea pigs, a similar phenomenon is poorly documented in man. Here we report the study of three human autoreactive T cell clones isolated during immunization of HLA-DRw13 donors either against influenza A/Texas virus or against allogeneic cells. These clones are specific for autologous HLA-class II specificities either common to all HLA-DRw13 molecules or restricted to the HLA-DR products specific for the DW19 subtype of HLA-DRw13. They are also cytotoxic and they have the same specificity when tested for lytic activity or in proliferation assays. Furthermore, they are also able to help autologous B cells to polyclonally produce Ig. The possible implication of such clones in regulatory mechanisms involving HLA-class II molecules is discussed.

Adult↗
PubMed1987

[Boutonniere deformity].

This paper was presented at the 1986 Congress of the GEM, as a teaching conference on treatment of the boutonniere deformity, based on the experience of the Nancy Hand Unit. The results of early treatment namely prevention of deformities and stiffness, are in most cases satisfactory, in contrast with late surgical correction which necessitates extensive exposure and tenolysis, and complicated repairs. Conservative rehabilitation and dynamic splinting should always precede, prepare and facilitate late operations, and sometimes avoids any surgery.

Arthrodesis↗