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Biomedical subjects

F Picard

Publications and source records attributed to F Picard.

At least 127 records · Page 7Linked to original sources
PubMed1994

[Mid-term results of 173 cases of surgery of the anterior cruciate ligament using the Mac Intosh procedure, reinforced by the Kennedy Ligament Augmentation Device].

UNLABELLED: This is a retrospective study of 173 chronic laxities of the knee operated on between May 1985 and December 1988 using the Mac Intosh procedure, reinforced by the Kennedy L.A.D. Follow-up was between 4-8 years and the same surgeon operated on all the knees. MATERIALS AND METHODS: 171 patients were operated on (113 men and 58 women) aged between 15-49 years (average age 26.5 years). The vast majority were sportsmen both at competition level (51 cases) and at recreational level (119 cases). The average time-span between accident and intervention was 15 months (1-240 months). In the pre-operative assessment, 80 cases (46.2 per cent) were found to have a grade II Lachman test and 91 cases (52.6 per cent), a grade III Lachman test; a positive pivot shift was found in more than 95 per cent of cases. There were lesions of the medial meniscus in 101 cases (58.4 per cent), of the lateral meniscus in 94 cases (54.4 per cent) and there was no meniscal lesion in only 41 cases (23.8 per cent). Finally there were 22 chondral lesions of the medial femoral condyle (12.7 per cent) and 7 of the lateral condyle (4.1 per cent). RESULTS: These were based on 159 cases (14 lost to follow-up before the third post-operative month), but only 107 (61.8 per cent) were reviewed by one of us (i.e. not the original surgeon). Tolerance of the L.A.D. was excellent. There was no sign of synovitis or joint effusion persisting beyond 1 year. Furthermore, there were no serious complications (no sepsis, only 4 cases (2.3 per cent) of joint stiffness, 2 cases of reflex sympathetic dystrophy and 5 cases of sural phlebitis (2.9 per cent). Moreover, the few minor complications that arose resolved with the appropriate treatment. Anatomical results, evaluated using. Lachmans test (maximum manual Lachman measured with the Bercovy Laximeter) showed 24 cases (22.4 per cent) with zero differential residual laxity, 54 cases (50.5 per cent) with a differential laxity of between 0-2 mm; 20 cases (18.7 per cent) with a laxity of between 2-4 mm and in 9 cases (8.4 per cent) a laxity of greater than 4 mm. Functional results, using the Arpège C.L.A.S. system showed good results in 83 per cent (score > and unsatisfactory results in 17 per cent of cases. The long time-span between intervention and subsequent review with the C.L.A.S. system should be taken into account. However, the proportion of competitive sportsmen to recreational sportsmen was practically identical when comparing pre-traumatic figures (C = 29.5 per cent, R = 68.8 per cent) to figures at the time of follow-up (C = 21 per cent, R = 69.5 per cent). Radiological results (A.P. and Schuss films) showed 63 knees (58.9%) with no signs of either medial or lateral, preliminary or full-blown, femoro-tibial osteo-arthritis. DISCUSSION: With an average follow-up of > 5 years (4-8 years), it is possible to say that ligamentoplasty of the anterior cruciate ligament using the Mac Intosh procedure reinforced with the Kennedy L.A.D. is not causative of any iatrogenic problems. The anatomical results were totally satisfactory (almost normal) in 72.9 per cent of cases; the radiological results showed ""normal'' knees in 58.9 per cent of cases and functional results were identical to results obtained using many other techniques.

Adolescent↗
PubMed1993

Molecular analysis of T-cell receptor V beta chains of human T-cell chronic lymphocytic leukemia does not show intraclonal variability: implications for immunotherapy.

Human T-cell chronic lymphocytic leukemia (T-cell CLL) is a heterogeneous disease characterized by a monoclonal malignant proliferation of T cells in which the T-cell receptors (TCRs) can be, when expressed, considered to be membrane tumor-specific antigens. Owing to the increasing number of available monoclonal antihuman TCR reagents, it could be of interest to evaluate the feasibility of anti-TCR treatment during T-cell CLL. To test the therapeutic potentiality of anti-TCR monoclonal antibodies, we first analyzed the intraclonal variability in two terminally ill patients suffering from TCR alpha beta-positive cell CLL bearing different immunophenotypes. The cDNA corresponding to the variable regions of the TCR beta chains originating from the malignant T cells were amplified, cloned into M13 phages, and sequenced. The sequence analysis of multiple independent clones showed no intraclonal variability, with no evidence for ongoing hypermutation in the V beta region genes. The relevance of these findings with regard to an anti-V beta therapy and the comparison with similar analysis during B-cell monoclonal lymphoproliferations are discussed.

Antigens, CD↗
PubMed1993

High doses of intravenous recombinant erythropoietin for the treatment of anaemia in myelodysplastic syndrome.

We studied the efficacy of high doses (100,000 IU intravenously (IV)/twice a week) of human recombinant erythropoietin (rHuEpo) in patients with transfusion dependent myelodysplastic syndromes (MDS). Rationale for such dose of IV Epo was the poor in vitro response of MDS erythroid progenitors (CFU-E) to physiological concentrations of Epo, and the usual high endogenous serum Epo levels of MDS patients. Seventeen patients (nine males, eight females) were included, five refractory anaemia (RA), six RA with blasts excess (RAEB), five RA with ringed sideroblasts (RARS). Tolerance was good, except in three patients who experienced severe flu-like syndrome after Epo injection. None of the patients showed hypertension or developed anti rHuEpo antibodies. Three patients (17.6%) with RAEB had 35-60% reduction of transfusion requirements. No progression of disease occurred. Percentage of erythroblasts, endogenous baseline Epo level and in vitro cultures of erythroid progenitors did not correlate with response to Epo treatment. This study shows that very high IV doses induce only seldom and partial improvement in the status of transfusion dependent MDS. This rate of response, not higher than described with lower dosage, probably represents the maximum expectable response to rHuEpo in this category of patients.

Adult↗
PubMed1992

Use of the new Coulter MAXM for leucocyte differentials.

The Coulter MAXM is an automated instrument designed to give a complete haematological profile including cell counts and WBC differential (DIFF). The WBC DIFF is determined by tridimensional flow cytometry on the basis of cell volume, light scattering and conductivity (VCS technology). Evaluation of the MAXM DIFF was performed by comparison with microscopic examination of blood smear. A total of 467 samples were studied by the MAXM and reference techniques, according to a standard protocol employed in our laboratory to define the criteria for smear examination. Good correlation was obtained between the two methods in non-flagged samples and those flagged only with an isolated "Imm Gran" message. In a group of 407 non-haematological and 60 haematological patients, there were 12 (2.6%) false positive and 5 (1.1%) false negative reports, all in non-haematological cases and the five false negative results corresponding to no more than minor abnormalities. The Coulter MAXM was thus shown to be an excellent haematology analyser. This instrument was capable of detecting significant abnormalities of blood smears with a sensitivity of 97.9%, a specificity of 94.7% and a global efficiency of 96.3% in the samples examined in the present study.

Automation↗
PubMed1992

[Myelitis caused by toxocara canis (larva migrans)].

A young woman presented with recurrent myelitis associated with persistent eosinophilia in blood and CSF. Specific serological procedures in blood and CSF led to the diagnosis of visceral larva migrans. The patient recovered after 21 days of treatment with diethylcarbamazine. To our knowledge, this is the second report of myelitis in the course of visceral larva migrans.

Adult↗
PubMed1991

Abnormalities of T lymphocyte subsets in systemic sclerosis demonstrated with anti-CD45RA and anti-CD29 monoclonal antibodies.

T cell subpopulations were assessed by two colour flow cytometry with phycoerythrin conjugated anti-CD45RA and anti-CD29 and fluorescein conjugated anti-CD4 and anti-CD8 monoclonal antibodies, on peripheral blood lymphocytes from 12 patients with systemic sclerosis and from nine control subjects. The percentage of CD4+CD29+ cells was significantly higher in patients with systemic sclerosis than in controls (mean (SEM) 68.8 (3.1) v 47.9 (4.1) respectively). CD4+CD45RA+ cells were not significantly different in patients and controls. CD8+CD29+ and CD8+CD45RA+ subpopulations were significantly higher in patients with systemic sclerosis than in controls (83.0 (3.2) v 58.7 (6.8) and 80.2 (3.0) v 66.9 (3.2) respectively). The increase in the percentage of CD29+ cells suggests an activation of memory cells in patients with systemic sclerosis, which may play an important part in the pathogenesis of the disease.

Antibodies, Monoclonal↗
PubMed1990

Acute T-cell leukemia/lymphoma mimicking Hodgkin's disease with secondary HTLV I seroconversion.

The authors observed a pleiomorphic lymphoma mimicking Hodgkin's lymphoma in a French Guyana black woman lacking antibodies for human T-cell lymphoma/leukemia virus type I (HTLV I). After two courses of chemotherapy with either mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) or doxorubicin, bleomycin, vincaleukoblastine, and dacarbazine (ABVD), a typical acute T-cell leukemia/lymphoma developed with HTLV I seroconversion. Specific HTLV I DNA sequences were detected using the polymerase chain reaction (PCR) on a lymph node biopsy obtained before chemotherapy. The mechanisms of the seroconversion are discussed.

Adult↗
PubMed1990

Changes in blood leucocyte populations induced by acute maximal and chronic submaximal exercise.

Absolute (x 10(3).mm-3) or relative (%) numbers of blood leucocyte types (monocytes, lymphocytes, neutrophils) and lymphocyte subsets (T11+, T4+, T8+, B1+, and NKH1+) reacting with specific monoclonal antibodies were determined at rest, immediately after maximal exercise on a treadmill, in six controls (C), and in six young cyclists before training (BT) and after 5 months of training (AT). Maximal exercise significantly increased the absolute number (mobilization) of virtually all the types of leucocytes and subsets of lymphocytes in C, BT and AT subjects. In these subjects mobilization of natural killer cells (NKH1+) and cytotoxic/suppressor T lymphocytes (T8+) was greater than mobilization of the other leucocyte types and lymphocyte subsets; however, maximal exercise induced no significant changes in the relative numbers of any leucocyte types and lymphocyte subsets, except in the case of T4+ lymphocytes in At cyclists. Chronic submaximal exercise induced increased mobilization of neutrophils and decreased mobilization of lymphocytes during maximal exercise, except in the case of B lymphocytes (B1+) and NKH1+ cells, and decreases in the absolute and relative number of neutrophils at rest. It remains to be seen how these results can explain the modifications of leucocyte activities noted in vitro after isolated or chronic exercise.

Adult↗
PubMed1990

Use of Coulter VCS for differential leukocyte counts.

The Coulter VCS is a tridimensional flow cytometer designed for differential leukocyte counting on the basis of cell volume, light scatter and conductivity. The VCS differential performed on 192 non-flagged samples was compared with the blood smear, taken as the reference method. A good correspondence was found between the two methods. Two hundred and seventy pathological samples were studied by both the VCS and the reference method: 219 samples with no anomalies other than quantitative changes and 51 with abnormal cells. 41% of the quantitative changes presented without any flag; 59% were flagged: either isolated X5 flags (30%) or other flags needing blood smear review (29%). Samples with abnormal cells (51) were detected with one or more flags: X3 + X6 in myelocytic disease X2 + X7 in lymphocytic disease. Only two (1 hairy cell leukemia, 1 lymphoma) were not flagged; however in these cases the abnormalities were revealed by the presence of either a striking neutropenia or a lymphocytosis. This corresponded to a false-negative rate of 0.4% in the group studied. Further studies were performed on patients with X5 flagging only. The VCS differential was compared to the optical differential as a reference method. There was a good relationship between the two methods; thus X5 flagging could be established without further slide review provided the numerical values were within the range valid for the laboratory. Thus, in our system of working, both VCS flags (except isolated X5) and laboratory performance limits were taken into account as regards the need for blood smear review. This resulted in a review rate of 15%.

Data Display↗
PubMed1989

Recombinant bovine interferon-gamma enhances expression of class I and class II bovine lymphocyte antigens.

Recombinant bovine interferon-gamma augments expression of class I and class II histocompatibility antigens on the surface membrane of bovine lymphocytes. Immunofluorescence techniques using a series of monoclonal anti-HLA antibodies demonstrate that this enhancement is detectable as early as 24 h after incubation with rBoIFN, while maximum surface expression is obtained within 3-5 days. A concentration as low as 10 units of rBoIFN is effective. Such results may be useful for characterizing the BoLA gene products.

Animals↗
PubMed1989

A virus-specific CD4+ cell-mediated cytolytic activity revealed by CD8+ cell elimination regularly develops in uncloned human antiviral cell lines.

Antiviral HLA class II-restricted cytotoxic CD4+ clones have been relatively well characterized in vitro but their significance in the immune response remains unknown. Here anti-influenza A and anti-EBV CD4+ CTL have been studied by using permanent cell lines either untreated or depleted of CD8+ cells. In bulk cultures, HLA class I-restricted anti-viral CD8+ CTL account for all of the detectable killer cell activity, whereas after elimination of CD8+ cells an HLA class II-restricted killer activity mediated by CD4+/2H4-/4B4+ cells was consistently observed. The CD4+ CTL were fully differentiated in all of the cultures tested from the third in vitro passage because they could be demonstrated immediately after elimination of CD8+ cells. These CD4+ killer cells were equivalent to the CD8+ cells in terms of their lytic capacity. The absence of any class II-restricted antiviral activity in bulk cultures seems to be related to the very small numbers of CD4+ cells present in these antiviral cell lines. However, CD4+ cytolytic activity could not be detected during the first two in vitro passages, even when limiting dilution analysis of the CTL precursors were performed, showing that the killer function of Th cells differentiate only after several in vitro stimulations.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Role of different lymphocyte subsets in human anti-viral T cell cultures.

We have systematically studied uncloned human cell lines derived from anti-influenza A virus or anti-Epstein-Barr virus (EBV) bulk cultures, or from cultures highly enriched for CD4+ or CD8+ lymphocytes. The most noteworthy results are the following: (1) Anti-viral bulk cultures consisted of more than 90% of CD8+ cells in all cases. In contrast, anti-HLA cell lines are composed of approximately 50% CD8+ and 50% CD4+ cells. All of the CD8+ and CD4+ cells present in the culture were also 4B4+/2H4-. (2) In anti-viral bulk cultures, the cytolytic activity was restricted by HLA class I molecules and almost exclusively through a single HLA class I molecule. (3) Positively or negatively selected CD8+ lines showed the same restriction pattern. They grew less efficiently than bulk cultures but could be maintained in the absence of CD4+ cells. The CD4+ cells were however necessary at the beginning of the culture for the development of cytolytic anti-influenza virus CD8+ cells, whereas they were not required for the development of cytolytic anti-EBV CD8+ cells. (4) The CD4+ cell lines grew more actively than bulk cultures. A cytolytic activity for virus-infected cells was constantly detected in these culture from the third passage onward and it was always restricted by HLA class II molecules. This activity was maintained throughout the culture period. However, class II-restricted cytolytic cells were not detected during primary or secondary responses in vitro.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

[Indications for therapeutic interruption of pregnancy in Ille-et-Villaine from 1982 to 1986. Apropos of 222 cases].

The authors have made the census of all the Medical Terminations of Pregnancy (MTP) which have been carried out in the Department of Ille et Vilaine from 1982 to 1986, i.e. 222 cases, in order to precise the different indications and the diagnosis tools which were used. 132 MTP concern women who live in the Department of Ille et Vilaine. By referring this figure to the total number of pregnancies in this area, one can see that the average incidence is of 1.9%; MTP account for 1% of the total number of Terminations of Pregnancies. Foetal indications are more frequent (188 cases; i.e. 84.7%) than maternal ones (34 cases, 15.3%); these figures remained stable over the 5-year period of study. Chromosomal aberrations and closing defects of the neural tubule are the main causes of MTP (22.9% of foetal indications). Among the 43 chromosomal aberrations, trisomies are the most frequent ones (34.9%) because all women aged 38 or more are proposed a detection. The diagnosis of trisomy was made in 24 cases after tests were programmed either because of the age of the mother or because of family antecedents (amniocentesis: 22 times, punction of foetal blood: once, biopsy of chorion villosities: once), in 6 cases after tests were carried out on the basis of suspect clinical signs amniocentesis: once, punction of foetal blood: 5 times), and in 13 cases after the echography had revealed a major syndrome. Closing defects of the central nervous system mainly concern anencephaly (17.6% of foetal indications) since the echography enables an easy diagnosis. All anencephaly have actually been detected during the reference period of pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Abnormalities, Multiple↗