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M Bailly

Publications and source records attributed to M Bailly.

At least 55 records · Page 3Linked to original sources
PubMed1994

Expression of PNA-binding sites on specific glycoproteins by human melanoma cells is associated with a high metastatic potential.

Lectin-binding patterns of seven human melanoma clones and variants selected from the same parental cell line and differing in their spontaneous metastatic potential in an animal model were compared by flow cytometry and Scatchard analysis. Human melanoma clones and variants with high and low metastatic potential could be distinguished by their peanut agglutinin (PNA)-binding patterns, but not by their wheat germ agglutinin (WGA)-, Ulex europaeus agglutinin I (UEA I)-, and soybean agglutinin (SBA)-binding patterns. Low metastatic clones and variants proved to be made up of single poorly peanut agglutinin-binding cell population (2.20-3.52 x 10(6) sites/cell, Ka = 2.48-2.75 x 10(6) M-1). By contrast, highly metastatic variants were found to be constituted by two cellular subpopulations, exhibiting respectively a moderate 2.62-3.72 x 10(6) sites/cell) and a high peanut agglutinin staining (17.68-18.76 x 10(6) sites/cell). One highly metastatic clone was found to be homogeneously constituted by a single population of cells strongly binding this lectin (18.86 x 10(6) sites/cell) with an association constant of 4.06 +/- 10(6) M-1. Using an EPICS V cytometer, these two subpopulations were sorted from a highly metastatic variant and tested for their metastatic abilities: cells with high PNA binding generated a higher frequency of metastases than did moderately PNA-binding cells. Following treatment with Vibrio cholerae neuraminidase, all cells from all variants and clones were brightly labeled by PNA, collecting in a single peak with similar fluorescence intensities. Electrophoresis of total cellular proteins and subsequent detection with labeled PNA om Western blots show two major PNA-reactive glycoproteins with apparent molecular weights of 140 and 110 kDa (MAGP1 and MAGP2), expressed only in highly metastatic cells, but which can be strongly labeled by PNA in slightly metastatic cells following a treatment with neuraminidase. These results provide evidence that the expression of terminal galactose (beta 1-3)N-acetyl galactosamine structure, positioned on MAGP1 and MAGP2 glycoproteins, is associated with the metastatic potential of human melanoma cells.

Arachis↗
PubMed1994

Human melanoma cell lines differ in their capacity to release ADP and aggregate platelets.

In this study we have investigated, using three different human melanoma cell lines (M1Do., M3Da., M4Be.). the varying capacity of melanoma cells to induce platelet aggregation in the presence or absence of inhibitors of ADP or thrombin. The expression levels of different integrins (alpha v, beta 3, alpha v beta 3, alpha IIb, alpha v beta 3) were evaluated by immunoprecipitation, binding and flow cytometry studies. The level of ADP in supernatants of melanoma cells were quantified by ADP bioassay and HPLC. Platelets were irreversibly aggregated by M3Da, as shown by electron microscopy, in contrast to M1Do, which induced a slow reversible aggregation. M4Be. did not induce platelet aggregation. In both cases, with M3Da. or M1Do., apyrase but not PPACK inhibited platelet induced aggregation. An anti-alpha v beta 3 monoclonal antibody (LYP18) or polyclonal antibody inhibited platelet aggregation. A similar number of LYP18 molecules bound to the surface of M1Do., M3Da. and M4Be. cell lines. Biological HPLC assays of ADP present in the supernatant of tumour cell lines showed the highest concentration of ADP to be secreted by M3Da., followed by M1Do., and none detected for M4Be. These results show that differences in in vitro aggregating potential of the three human melanoma cell lines are not related to low integrin expression levels but to their ability to generate ADP. Generation of ADP by human melanoma cells may act as important modulator of melanoma-platelet interactions.

Adenosine Diphosphate↗
PubMed1994

Selective expression of PNA-binding glycoconjugates by invasive human melanomas: a new marker of metastatic potential.

Alterations of cell-surface glycoconjugates have been associated with invasiveness and metastatic capacity in a number of experimental and human tumors (bladder and colon cancer). We have recently shown that human melanoma cells from variants selected for high metastatic potential in an animal model bind the lectin peanut agglutinin (PNA), and that human melanoma cell populations enriched for PNA binding cells generated a higher frequency of metastases when xenografted into immune suppressed neonatal rats. We have therefore sought cells binding PNA in biopsied human melanocytic tumors and compared frequencies of PNA binding by cells from benign nevi, early and late primary melanomas, and metastatic melanomas. Sections of conventionally processed tissues were deparaffinised and exposed to biotinylated PNA; PNA fixation was revealed by the avidine/peroxidase/AEC technique. In 51 specimens tested, PNA appears to react electively with invasive tumors, since only one of the 7 early primary melanomas (Clark I-II) reacted while 13/23 late primary melanomas (Clark III-V), and 4/21 melanoma metastases were reactive. In addition, only 1/17 benign nevi bound PNA. In primary tumors, the reactive cells were exclusively invasive tumors cells in the dermis. PNA reactive material was observed in the cytoplasm and plasma membrane of reactive cells. Hence, alterations in composition and cellular localisation of glycoconjugates detectable by lectin histochemistry in melanoma cells may be markers of metastatic potential that may be applicable on an individual patient basis.

Animals↗
PubMed1994

[Evaluation of a new commercial kit for emergency determination of serum myoglobin].

The usefulness of a nephelometric-based serum myoglobin assay kit in the early diagnosis of acute myocardial infarction was assessed in 92 consecutive patients admitted within 24 hours of the onset of spontaneous chest pain lasting > or = 20 minutes. The discharge diagnosis was acute myocardial infarction in 37 patients (40.2%), myocardial infarction lasting > or = 6 hours in 10, and no myocardial infarction in 45 (48.9%). The characteristic curve showed that the best differential diagnostic value was a serum myoglobin > or = 130 micrograms/l (sensitivity, 75.6%; specificity, 91.7%; positive-predictive value, 88%; negative-predictive value, 82%). The initial diagnosis was doubtful in 33 patients (36%) because of an inconclusive electrocardiogram. A serum myoglobin value of > or = 130 micrograms/l would have identified 9 of the 13 patients with acute myocardial infarction and all of the 20 patients without myocardial infarction, giving an accuracy of 84.8%. These results suggest that this new rapid, quantitative serum myoglobin assay would be useful in the evaluation of suspected myocardial infarction, especially in patients with an inconclusive electrocardiogram.

Aged↗
PubMed1993

Accumulation of heparan sulfate in the culture of human melanoma cells with different metastatic ability.

Glycosaminoglycans were metabolically labeled in subconfluent cultures of highly metastatic 7Gp122 and poorly metastatic IC8 variants and of the low metastatic parental M4Be human melanoma cell line. Proteoglycans were separated by DEAE Trisacryl chromatography from the culture medium, from the heparin extract of the cell layer and from the heparin-extracted cell residue lyzed with detergents. Glycosaminoglycans were released from the proteoglycans by reductive alkaline hydrolysis and heparan sulfate (HS) was detected by deaminative cleavage with nitrous acid. Expressed on cell protein basis, the labeled HS content in the medium and in the cell layer decreased with increasing metastatic ability. The extraction of HS with heparin from the 7Gp122 cells indicated that this variant was enriched in (polypeptide bound) HS non inserted into the plasma membrane, compared with the low metastatic IC8 and M4Be cells. The HS fraction in heparin extract and in the heparin-extracted cell residue exhibited molecular mass heterogeneity on gel permeation chromatography and it contained HS fragments. Scission with nitrous acid followed by molecular sieve chromatography of the degradation products indicated that the tetra- and disaccharide repeats separated by the N-sulfated glucosamine residue were present in about equal amounts and constituted 60% of the HS chains in the IC8 and M4Be cells. HS from 7Gp122, IC8 and M4Be cells did not bind antithrombin III with high affinity but it was capable of binding bFGF in in vitro assay.

Antithrombin III↗
PubMed1993

Monoclonal antibody accumulation in experimental and spontaneous lung metastases of human malignant melanoma in rodents.

Monoclonal antibody (mAb) uptake in metastatic lung lesions was depicted and evaluated by digital autoradiography. The models examined were experimental metastases of a human melanoma in nude mice and spontaneous metastases of human melanoma in immunocompromised young rats. By comparing uptake patterns in local (s.c.) tumours and in lung processes of various sizes it was found that patterns were essentially similar in both types of malignant tissue. From the point of view of visualization, however, the high blood content of lung tissue resulted in high background and low contrast. This could be overcome by the use of rapidly cleared antibody fragments.

Animals↗
PubMed1993

Increased spontaneous mutation rates and prevalence of karyotype abnormalities in highly metastatic human melanoma cell lines.

Previous studies have suggested that increased malignant potential might be related to increased genomic instability, but this issue still remains controversial. We tested this hypothesis in a human tumour spontaneous metastasis model, using six clones and variants isolated from the parental poorly metastatic M4Be melanoma cell line, and expressing various metastatic abilities. The spontaneous rates of mutation to ouabain resistance measured in these cells by Luria and Delbrück fluctuation analysis correlated with the metastatic ability of the cells: moderately and highly metastatic cells showed spontaneous mutation rates 10 to 50 times higher than those of poorly metastatic cells. Genomic instability at the chromosome level was assessed by searching for accumulated structural abnormalities in the moderately and highly metastatic cell lines. All the cell lines appeared hypertriploid, and showed comparable modal numbers and great chromosome dispersion. Unstable DNA amplification in the form of double minute chromosomes was shown in one of the four poorly metastatic cell lines, and in a significantly higher proportion of the cells of two of the three metastatic cell lines. Abnormal chromosomes were demonstrated in all cell lines, with markers involving specific rearrangements of chromosomes 1, 6, 7, 8, 9, 11, 14 and 15, as frequently observed in human melanoma cells. Clonal markers were present in all cell lines, documenting the common origin of all variants and clones, and specific marker amplification was noticed in highly metastatic cells compared to poorly metastatic lines. These results suggest that human tumour progression might be accompanied both by an increase in genomic instability and by accumulation of karyotypic abnormalities.

Cell Division↗
PubMed1993

Characterization of quail Pax-6 (Pax-QNR) proteins expressed in the neuroretina.

After differential screening of a cDNA library constructed from quail neuroretina cells (QNR) infected with the v-myc-containing avian retrovirus MC29, we have isolated a cDNA clone, Pax-QNR, homologous to the murine Pax-6, which is mutated in the autosomal dominant mutation small eye of mice and in the disorder aniridia in humans. Here we report the characterization of the Pax-QNR proteins expressed in the avian neuroretina. From bacterially expressed Pax-QNR peptides, we obtained rabbit antisera directed against different domains of the protein: paired domain (serum 11), domain between the paired domain and homeodomain (serum 12), homeodomain (serum 13), and carboxyl-terminal part (serum 14). Sera 12, 13, and 14 were able to specifically recognize five proteins (48, 46, 43, 33, and 32 kDa) in the neuroretina. In contrast to proteins of 48, 46, and 43 kDa, proteins of 33 and 32 kDa were not recognized by the paired antiserum (serum 11). Paired-less and paired-containing proteins exhibited the same half-life (6 h) and were phosphorylated mostly on serine residues. Immunoprecipitations performed with subcellular fractions of neuroretinas showed that the paired-containing proteins were located in the nucleus, whereas the 33- and 32-kDa proteins were found essentially in the cytoplasmic compartment. However, immunofluorescence experiments performed after transient transfections showed that p46 and p33/32 were also located in vivo into the nucleus. Thus, the Pax-QNR/Pax-6 gene can produce proteins with two DNA-binding domains as well as proteins containing only the DNA-binding homeodomain.

Animals↗
PubMed1993

[Retrospective evaluation of an intra-uterine insemination program with donor].

The results of 109 intra-uterine inseminations with cryopreserved prepared donor semen (IUId) in stimulated cycles, performed among 42 couples from November 1987 to June 1991, were analysed. The single IUId was performed 39 +/- 3 hours after the injection of human chorionic gonadotrophin. For each IUID 1,25 +/- 1.4 x 10(6) motile spermatozoa (mean +/- standard deviation) were inseminated. 27 pregnancies were obtained and the pregnancy rate per cycle was 24.8%. The number of motile spermatozoa inseminated was significantly higher in the group of pregnant women than in the population without pregnancy (1.64 x 10(6) x 10(6)/IUI versus 1.13 x 10(6)/IUI). The sperm count and the number of motile spermatozoa inseminated were significantly higher when the semen was prepared on discontinuous Percoll gradients than after swim-up in Menezo B2 medium (8.2 x 10(6)/ml versus 4.3 x 10(6)/ml and 1.7 x 10(6) versus 0.77 x 10(6)). Among the 27 clinical pregnancies, 3 were twins and 2 were triplets. The ovarian hyperstimulation associated with the use of a prepared semen of donor, generate a high risk of multiple pregnancies. To improve the results without increasing the risk of multiple pregnancies, we propose to inseminate about 1.5 x 10(6) motile spermatozoa with a maximum plasma estradiol level of 1 100 pg/ml, on the day of hCG injection, associated with 2 preovulatory follicles. This technique may augment the rate of pregnancy and represents an appreciable time gain. These results must be confirmed by randomized prospective studies.

Adult↗
PubMed1992

Laminin expression by two clones isolated from the colon carcinoma cell line LoVo that differ in metastatic potential and basement-membrane organization.

In the present report we describe the characteristics of 2 clones, E2 and C5, isolated from the human colon adenocarcinoma cell line LoVo. When grafted to immunosuppressed newborn rats, these clones formed tumors that varied with regard to differentiation rate, basement-membrane organization and lung metastatic potential. Production and distribution of laminin by E2, C5 and related tumors was studied by immunohistochemistry with an anti-laminin monoclonal antibody 4C12 (MAb 4C12). In lowly metastatic E2-derived tumors, strong regular stainings were observed which were strictly peri-tumoral and corresponded to the basal lamina. Since the antibody interacted with human laminin (the graft) but not with rat laminin (the host), this result indicated that basement-membrane laminin was supplied mainly by tumor-cell synthesis. In highly metastatic C5-derived tumors, the staining obtained with MAb 4C12 was peri-cellular and unorganized. Laminin synthesis by E2 and C5 cells in sub-cultures or soon after dissociation from explanted tumors was studied by metabolic labelling with 35S-methionine under steady-state conditions followed by immunoprecipitation and SDS-PAGE. High-molecular-weight laminin comprised by disulfide-linked A and B chains, i.e., heterotrimeric laminin, was found in cell lysates and in the secretion medium of cell lines and tumor cells. In addition, B1B2 dimers and free B chains were observed in cell lysates. Quantitatively, laminin expression by E2 and C5 clones or tumor cells was not significantly different. These findings suggest that basement-membrane defects in invasive clone LoVo C5 were not due to laminin under-expression.

Animals↗
PubMed1992

[Dispersion of biochemical analysis results in Dakar: preliminary results].

Now and then, the conflicting character of results of some analyses is prejudicial to patients (financial and particullary psychological repercussions), to the laboratories (renown) and to the practitioners (difficulties of interpreting). After a study of the dispersion of some analyses results, the authors propose a creation of an Interlaboratory Quality Control in Clinical Biochemistry in Senegal.

Chemistry, Clinical↗
PubMed1992

[Ambulatory and hemodynamic treatment of venous insufficiency (CHIVA cure). Report of an atypical case].

After a brief introduction describing the principle, strategy and tactics of hemodynamic treatment of venous insufficiency in ambulant patients, the following atypical case is described. Ms P., aged 38 years, presented a functional symptomatology including waking at night and was obliged to get out of bed. Varices were moderately visible but she asked for treatment for esthetic reasons. A future pregnancy was discounted. Clinical examination and the pulsed ultrasound-Doppler cartogram showed incontinence of the internal perineal, opening from the genitofemoral fold and rejoining the summit of Jacomini's vein arch. The dorsal segment of Jacomini's vein was incontinent with a retrograde flux and rejoined an incontinent short saphenous continuing as a type III shunt. The cartogram obtained, the strategy decided and the intervention carried out on 19 June 1990 are illustrated by photographs. At 4 month follow up and despite the heat wave of summer 1990, all functional signs had disappeared and a sufficiently esthetic result had been obtained. Unexpectedly, the patient announced that she was pregnant.

Adult↗
PubMed1991

Human tumor spontaneous metastasis in immunosuppressed newborn rats. II. Multiple selections of human melanoma metastatic clones and variants.

Using a recently developed model of human tumor spontaneous metastasis in immunosuppressed newborn rats, we selected variants with different metastatic abilities from the human melanoma cell line M4Be. We used 4 in vivo selection approaches, by direct serial tumor transplantations or by techniques involving in vitro reculture of the cells recovered from s.c. tumors or lung and lymph-node metastases. In addition, 3 series of clones were derived in vitro from the M4Be cell line, either by limiting-dilution or by cloning in semi-solid agar and harvesting small and large colonies. A considerable amount of heterogeneity in tumorigenicity and metastatic ability was demonstrated among variants and clones following in vivo selections and in vitro cloning. Four main malignant phenotypes were identified among those expressed by the selected cells: poorly tumorigenic and poorly metastatic; poorly tumorigenic and highly metastatic; highly tumorigenic and poorly metastatic; and highly tumorigenic and highly metastatic. However, while malignant phenotype (i.e., tumorigenicity and metastatic ability) did not appear to be grossly influenced by in vitro cloning procedure, it appeared greatly influenced both by the in vivo selection procedure (direct transplantations or use of in vitro culture between the in vivo passages) and by the origin of the cells under selection (s.c. tumor or metastases). Our study provided us with a large panel of variants and clones with varying metastatic abilities, which represent a model of human melanoma spontaneous metastasis allowing the study of critical determinants in human tumor metastasis.

Animals↗
PubMed1991

Human tumor spontaneous metastasis in immunosuppressed newborn rats. I. Characterization of the bioassay.

We characterize a new model of spontaneous metastasis of human tumor cells using anti-thymocyte serum (ATS) immunosuppressed newborn rats. We analyzed the intrinsic value of the bioassay of measurement of tumorigenicity and metastatic capacity using 17 human tumor cell lines, of which were 9 human malignant melanomas. Most of these cell lines revealed as tumorigenic and metastatic in lungs and/or lymph nodes 3 weeks after s.c. injection in the ventral flank of newborn rats, irrespective of their origin. All the melanoma cell lines that we injected were tumorigenic and 77% were metastatic, whereas the same cell lines grafted in nude mice showed no evidence of metastases after 6 weeks' examination. We were not able to show any relationship between tumorigenicity in nude mice and the malignant behavior of these cells in ATS-treated newborn rats. Likewise, neither chromosome abnormalities, nor antigenic marker expression were found to be related to tumor growth in nude mice or newborn rats. Two intrinsic parameters of the model were studied: number of cells injected vs. dose of ATS injected for one melanoma cell line; and role of the 3rd and 4th injections of ATS in the establishment and development of pulmonary metastases. Moreover, we show that s.c. injection in the ATS-treated newborn rat may represent a suitable method for studying melanoma cell tumor growth and spontaneous dissemination.

Animals↗
PubMed1991

Inducibility of lymphokine activated killer (LAK) cells in patients with acute myelogenous leukaemia in complete remission and its clinical relevance.

Peripheral blood mononuclear cells (PBMC) from 42 patients with acute myelogenous leukaemia (AML) in complete remission (CR) and from normal donors were activated into LAK cells in the presence of 1000 U/ml of recombinant interleukin-2 (rIL-2). Cytotoxicity of LAK cells was assayed against K562, Daudi, and Raji cell lines, and autologous and/or allogeneic thawed leukaemic blasts. Fresh unactivated PBMC from normal donors and AML patients served as controls. Mean +/- standard deviation (SD) percentage lysis of the different targets by patient LAK cells were: K562 61 +/- 20%, Daudi 62 +/- 23%, Raji 48 +/- 24%, autologous blast cells 12 +/- 16% and allogeneic blast cells 13 +/- 10%. Lysis of the different targets by LAK cells from normal donors was similar to that achieved with LAK cells from AML patients. Overall there was a good correlation between the lysis of the different targets. There was no significant difference between the percentage lysis of autologous and allogeneic thawed blast cells, although LAK cells from seven out of the 18 patients tested were unable to lyse autologous leukaemic cells. Activity of patient LAK cells did not correlate with the initial characteristics of the patient nor with the time spent in CR before harvesting PBMC for activation. At the time of analysis, 32 patients were in continuing CR and 10 had relapsed. Multivariant analysis for prognostic factors showed that patients whose LAK cells had more lytic activity on K562 (P = 0.005) and fresh blast cell (P = 0.02) targets had significantly less risk of relapse than patients with little inducible LAK cell activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Prostate-specific antigen. Interpretation of the results in relation to the sampling method].

The authors compare the two prostate specific antigen assay methods most widely used in France. The first method (RIA Baxter) uses an isotope marker (Iodine 125), the other (EIA Biotrol) uses an enzymatic marker (alkaline phosphatase). Prostate specific antigen was assayed by means of these two techniques in two groups of patients: one group of 49 men considered to be free of any prostatic disease, recruited from blood donors; another group of 89 male patients in whom a prostate specific antigen assay was performed prospectively at the first urology outpatients visit. The two prostate specific antigen assay techniques gave different results, but the values obtained by these two methods were not discordant. It is therefore possible to define a coefficient of proportionality of 1.45 regardless of the prostate specific antigen concentration or the urological disease considered (EIA Biotrol x 1.47 = RIA Baxter).

Adult↗