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C Fournier

Publications and source records attributed to C Fournier.

At least 19 recordsLinked to original sources
PubMed1995

Sequence analysis of a 33.1 kb fragment from the left arm of Saccharomyces cerevisiae chromosome X, including putative proteins with leucine zippers, a fungal Zn(II)2-Cys6 binuclear cluster domain and a putative alpha 2-SCB-alpha 2 binding site.

In the framework of the European BIOTECH project for sequencing the Saccharomyces cerevisiae genome, we have determined the nucleotide sequence of the left part of the cosmid clone 232 and the cosmid clone 233 provided by F. Galibert (Rennes Cedex, France). We present here 33,099 base pairs of sequence derived from the left arm of chromosome X of strain S288C. This sequence reveals 17 open reading frames (ORFs) with more than 299 base pairs, including the published sequences for ARG3, LIGTR/LIG1, ORF2, ACT3 and SCP160. Two other ORFs showed similarity with S. cerevisiae genes: one with the CAN1 gene coding for an arginine permease, and one with genes encoding the family of transcriptional activators containing a fungal Zn(II)2-Cys6 binuclear cluster domain like that found in Ppr1p or Ga14p. Both putative proteins contain a leucine zipper motif, the Can1p homologue has 12 putative membrane-spanning domains and a putative alpha 2-SCB-alpha 2 binding site. In a diploid disruption mutant of ORF J0922 coding for the transcriptional activator homologue, no colonies appeared before 10 days after transformation and then grew slowly. In contrast, haploid disruption mutants showed a growth phenotype like wild-type cells. One ORF showed weak similarity to the rad4 gene product of Schizosaccharomyces pombe and is essential for yeast growth. Five ORFs showed similarity to putative genes on the right arm of chromosome XI of S. cerevisiae. Two of them have similarity to each other and belong to a family of extracellular proteins that groups mammalian SCP/Tpx-1, insects Ag3/Ag5, plants PR-1 and fungi Sc7/Sc14.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosomes, Fungal↗
PubMed1995

Long-distance and long-term follow-up of a patient with intermittent Cushing's disease by salivary cortisol measurements.

Salivary cortisol is an excellent indicator of the plasma free cortisol concentration in normal and pathological situations. We took advantage of its ease of sampling, allowing multiple collections at home, to follow the course of a patient with Cushing's disease living in North Africa. This 48-year-old woman presented with a clinically moderate hypercortisolism caused by a large basophilic pituitary adenoma. Bilateral extension to the cavernous sinuses precluded surgical therapy. She went into spontaneous remission based on clinical signs as well as biochemical findings. During the following 2 years she demonstrated intermittent relapses that were treated by radiotherapy (50 Gy), followed by ketoconazole and then o-paraprime-dichloro-diphenyl-dichloroethane (Op'DDD). After a prolonged clinical remission, Cushing's syndrome again became active. Bromocriptine was started without effect and a new treatment with Op'DDD was began. Evaluation and follow-up were performed during hospitalizations and mainly through the measurements of salivary cortisol in more than 100 samples sent from North Africa by air mail to our department in Paris. Thus we were able to demonstrate intermittent overproduction of cortisol before any treatment, with periods of normal and even low values, and to follow the efficacy of therapy and to detect the relapses. We conclude that measurement of salivary cortisol is a valuable tool in difficult clinical situations such as intermittent hypercortisolism and remoteness between the patient and hospital.

Africa, Northern↗
PubMed1994

T cell regulation of collagen-induced arthritis in mice. III. Is T cell vaccination a valuable therapy?

Since T cells play a critical role in collagen-induced arthritis (CIA), CD4+ T cell hybridomas were derived from DBA/1 mice immunized with bovine type II collagen (CII). The hybrid clones selected were Thy-1-2+, CD4+, CD8-, T cell receptor (TcR) alpha beta + and produced interleukin-2 in response to CII peptides presented by I-Aq molecules. The clones were collagen type-specific and recognized CII from many species except the mouse. More precisely, the reactivity was directed against the immunodominant cyanogen bromide-cleaved fragment CB11(II). Analysis of the TcR carried by the T cell hybridomas showed that they used identical V alpha and J alpha (V alpha BMB, J alpha 20) gene segments and two distinct V beta (V beta 1 and V beta 4) associated with the J beta 2.5 gene segment. Interestingly, the junctional regions were highly conserved in structure and length. These findings may indicate a strong in vivo selection by the antigen for a particular combination of both alpha and beta chains of the TcR. Inoculation of irradiated anti-CII T cell hybrids into DBA/1 mice, before priming with CII, altered the course of the disease resulting in either a long-lasting suppression or an exacerbation of CIA whereas a control CD4+ hybridoma with an unrelated specificity did not influence the development of arthritis. However, the regulatory effect of anti-CII T cell clones was unpredictable, suggesting that the TcR structure may not solely account for the modulation of CIA and that T cell vaccination is not a reliable method for inducing suppression of CIA.

Amino Acid Sequence↗
PubMed1992

Biological activity and molecular interaction of a netropsin-acridine hybrid ligand with chromatin and topoisomerase II.

A hybrid molecule, which combines an anilinoacridine chromophore related to the antitumour drug amsacrine (m-AMSA) and a bispyrrole moiety analogous to the antiviral agent netropsin, has been examined for its ability to bind chromatin and to modulate the activity of topoisomerase II. The results show that the presence of histones does not alter the bimodal DNA binding process. Intercalation of the acridine and groove binding of the netropsin part of the drug are both observed with chromatin preparations. Moreover, the hybrid has a clear topoisomerase II-DNA cleavable complex-inducing activity close to that of m-AMSA. The role of the two parts of the hybrid ligand is discussed in relation to ternary complex formation. Two cell lines (L1210 leukemia and MCF7 mammary carcinoma) were compared in their sensitivity to the tested ligand. The drug, which appears to be an efficient growth inhibitor of leukemic cells in vitro, reveals moderate activity against P388 leukemia in vivo. The biological activity of the hybrid may derive from a mechanism that involves DNA binding and topoisomerase II inhibition. This study demonstrates that agents which intercalate and bind to the minor groove of DNA simultaneously represent a new class of drugs interfering with topoisomerase II and provide opportunities for the development of new antitumour agents.

Amsacrine↗
PubMed1992

Modification of the physicochemical and pharmacological properties of anticancer platinum compounds by commercial 5-fluorouracil formulations: a comparative study using cisplatin and carboplatin.

The influence of a commercial formulation of 5-fluorouracil (5-FU) on the stability and pharmacological properties of two platinum derivatives, cisplatin and carboplatin, was studied to determine whether the drugs could be mixed in containers or intravenous lines. When cisplatin was incubated in a French commercial formulation of 5-FU (Fluoro-uracile, Roche, France), high-performance liquid chromatographic (HPLC) studies demonstrated a rapid disappearance of the parent platinum compound, the extent of the degradation being 75% after 3.5 h. These studies also revealed that the degradation was not caused by a reaction between 5-FU and cisplatin but rather resulted from an interaction between cisplatin and trometamol, the excipient used in the French 5-FU formulation to buffer the solution at pH 8.2. The sole presence of trometamol in a cisplatin solution for 24 h at 30 degrees C resulted in the complete inhibition of both the ability of cisplatin to bind in vitro to human serum albumin and the antitumor activity of the cytostatic agent against P388 leukemia in mice (T/C% = 88% for cisplatin+trometamol vs greater than 333% for cisplatin). When cisplatin was incubated at the same pH in trometamol-free sodium hydroxide solutions (the excipient used in 5-FU formulations in several countries, including the United States and the United Kingdom), the parent compound was transformed into reactive species that were toxic to mice (T/C% = 40% in P388 leukemia). The degradation determined for a carboplatin-trometamol admixture using HPLC was similar to that found for cisplatin but occurred at a slower rate (0 after 3.5 h incubation and 55% after 24 h). The antitumor activity of carboplatin in P388-bearing mice was not significantly altered by a 24-h period of preincubation in the presence of trometamol (T/C% = 209% vs 241% for treatment with carboplatin in the absence of trometamol). As in the case of cisplatin, incubation of carboplatin for 24 h in a sodium hydroxide solution resulted in a toxic effect (T/C% = 64%). Our results thus demonstrate the incompatibility of both cisplatin and carboplatin with commercial formulations of 5-FU.

Animals↗
PubMed1992

Variations in the glycoforms of serum alpha 1-antichymotrypsin in liver diseases and after liver transplantation.

1. Using crossed immunoaffinity electrophoresis with free concanavalin A in the first dimension, we studied the microheterogeneity of alpha 1-antichymotrypsin due to various glycoforms in sera from patients with various liver diseases and after liver transplantation. 2. Studies by isoelectric focusing and immunoblotting and by crossed immunoelectrophoresis without concanavalin A in the first dimension allowed us to show that there is no dramatic variation in electrophoretic heterogeneity of alpha 1-antichymotrypsin in the serum of patients with liver diseases or after liver transplantation when compared with that of normal subjects. Therefore the heterogeneity observed in crossed immunoaffinity electrophoresis is due to various interactions with concanavalin A. 3. The results were expressed as the ratio of concanavalin A non-reactive glycoforms plus concanavalin A weakly reactive glycoforms to concanavalin A reactive glycoforms, called R alpha 1-ACT. R alpha 1-ACT was significantly higher in patients with cirrhosis (n = 53) when compared with normal subjects (n = 30). The median R alpha 1-ACT was 1 (range 0.72-1.25) in normal subjects. It was 1.6 (range 1.18-3.02), 1.45 (range 0.65-4.12) and 2.24 (range 1.03-19) in cirrhosis of Child's grade A, B and C, respectively. There was a dramatic decrease in glycoforms with mostly biantennary glycans in some patients with Child's grade C cirrhosis. Serum levels of alpha 1-antichymotrypsin were lower than normal only in some patients with Child's grade C cirrhosis. 4. Among the patients with acute viral hepatitis studied (n = 17), five were studied longitudinally.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Combination of cyclosporine A and calcitriol in the treatment of adjuvant arthritis.

We investigated combination treatment with cyclosporine A (CsA) and calcitriol (CT), 2 immunomodulatory agents, in vivo in the adjuvant arthritis (AA) model in rats. Treatment initiated at priming with complete Freund's adjuvant consisted of daily administration of CsA and CT during the prearthritic phase (14 days). CsA given alone delayed the onset of the disease, whereas the severity was either not affected or paradoxically enhanced. Injection of CT alone reduced the severity of arthritis. The association of low doses of CsA (5 mg/kg) and CT (0.2 micrograms/kg) further delayed the onset of AA and abolished the aggravating effect. Our findings suggest that low doses of CsA and CT in association exhibit the additive beneficial effects of either agent alone.

Administration, Oral↗
PubMed1992

Protective effects of ciprofloxacin against type II collagen induced arthritis in rats.

Ciprofloxacin, a new fluoroquinolone antibiotic, inhibits the in vitro production of interleukin 1 beta and tumor necrosis factor alpha by monocytes. We investigated its activity against type II collagen induced arthritis in rats. It exerted a dose dependent preventive effect at 50 and 75 mg/kg/day against clinical and histologic features of collagen induced arthritis without any influence on the production of anticollagen antibodies and alpha 1-acid glycoprotein. This effect was reversible after early removal of the treatment. Ciprofloxacin did not inhibit collagen induced arthritis in adrenalectomized rats but rather caused an exacerbation of the disease. Its effect was not modified by the simultaneous administration of an antiglucocorticoid, RU 40555.

Adrenal Cortex Hormones↗
PubMed1991

Experimental studies and preliminary clinical trial of vinorelbine-loaded polymeric bioresorbable implants for the local treatment of solid tumors.

Vinorelbine is a new 5' nor Vinca alkaloid, active by i.v. route, in various types of cancer disease such as non-small cell lung cancer and advanced breast cancer. In order to evaluate the possibility of using this drug for local treatment of cancer, Vinorelbine-loaded bioresorbable polymeric implants were prepared using a copolymer of D,L-lactic and glycolic acids (PLA 37.5 GA 25). According to the manufacturing process, the 1.2-mm-diameter cylindrical rods obtained had a drug content of 1, 5, or 20% (w/w) and released half of their content within about 6 days in vitro. In vivo release in rats was slower, half of the drug being released after about 14 days. A dose-dependent antitumoral effect was observed in mice (solid P388 leukemia model) when implants were administered into or in contact with the tumor. At highest drug loads and when administered soon after tumor implantation, Vinorelbine implants were more effective than i.v. administration (median survival time of treated animals related to untreated controls, greater than 360 versus 188). In dogs, results of toxicity experiments revealed that administration of implants in vital organs must be avoided. On the contrary, s.c. administration was well tolerated. A transient local necrosis was observed in the days following implantation, but normal skin was recovered after about 10 weeks. Thus, a clinical trial was conducted on patients with head and neck cancer; implantation of 20% loaded polymeric implants into the tumor sites succeeded in 8 of 9 patients. The sole failure was attributed to the unusual hardness of the tumor tissue. Except for a local transient inflammatory reaction (easily treated with nonsteroidal antiinflammatory agents), no other sign of toxicity was detected, and patients tolerated the device well. Fourteen days after implantation, patients underwent their planned surgery, and the implants were recovered. Residual drug content varied from 24 to 55%. In all cases, there was a clearly delimited necrotic area around the implant, ranging from 0.5 to 3.5 cm in diameter. In the smallest tumors, necrosis was also observed in the normal tissue inside this area. These results invite further studies to evaluate such drug-loaded polymeric implants.

Adult↗
PubMed1991

Therapy against murine collagen-induced arthritis with T cell receptor V beta-specific antibodies.

Immunization with native type II collagen (CII) of susceptible strains of mice (H-2q) induces a rheumatoid arthritis-like disease. Collagen-induced arthritis (CIA) is an experimental model for T cell-mediated autoimmune disease. To investigate the T cell receptor (TcR) repertoire involved in the pathogenesis of CIA, CII-primed DBA/1 mice were treated with various TcR V beta-specific monoclonal antibodies (mAb) using a protocol resulting in a long-term elimination of the target T cells. In vivo treatment with anti-CD4 mAb led to nearly complete protection against CIA. Mice injected with anti-V beta 8.1, 2 or anti-V beta 5.1, 2 mAb had a reduced incidence of arthritis (respectively 28.6% and 50% vs 84.6% for the control group). Administration of anti-V beta 2 mAb delayed the onset of the disease whereas injection of anti-V beta 6 or anti-V beta 11 mAb did not alter CIA. Moreover, the combined treatment with anti-V beta 2 and anti-V beta 5 mAb efficiently reduced the development of CIA. The humoral response to CII was down-regulated only in the groups of mice that were improved by the treatment. In vitro proliferative response to CII of lymph node cells from primed DBA/1 was partially blocked by addition of several anti-V beta mAb. Thus, our findings suggest that the overall T cell response to CII may be polyclonal while the T cell clones involved in the pathogenesis of CIA express a limited number of V beta chains.

Animals↗
PubMed1991

Modification of inflammatory processes by phenobarbital in rats.

Enzyme-inducing drugs such as phenobarbital (PB) increase serum concentrations of an acute-phase protein, alpha 1-acid glycoprotein (AGP), in man, dogs, and rats via an unknown mechanism. We studied the effects of PB on components of an acute inflammatory reaction in rats in order to determine if PB acts only on this biological marker of inflammation or is capable of altering the clinical course of inflammatory processes. Local carrageenan injection induces a similar time-dependent plantar edema and increases serum AGP levels in Sprague-Dawley (SD) and Dark Agouti (DA) rats. Pretreatment with PB for seven days modified neither parameter in SD rats while plantar edema was aggravated and serum AGP levels were increased in DA rats. The sedative-hypnotic properties of PB were not involved, since a single administration of this drug had no action in DA rats. On the other hand, chronic PB administration reduced the severity of an autoimmune disease, type II collagen-induced arthritis, in DA rats. These data indicate that PB, a potent inducer a cytochrome P-450-dependent enzymes, modifies the course of the inflammatory process. Preliminary results with macrophage transfer experiments suggest that this response to PB could be mediated by stimulated macrophages.

Acute Disease↗
PubMed1991

[Role of collagen conformation in type II anticollagen immunity in rheumatoid polyarthritis].

Type II anticollagen (CII) autoimmunity is a frequently reported, but non-specific, phenomenon in rheumatoid arthritis (RA). The authors show that in 88 sera samples from patients suffering from RA, the incidence of antibodies targeted against endogenous human CII was the same as that found for 149 control blood donors (14.8% versus 11.4%). However, a significant difference was found for the incidence of antibodies targeted against the alpha-chains of CII (26.1% versus 6.0%, p less than 0.001). As a result of investigating the specificity of the anti-CII antibodies in greater detail by means of an immunoprinting of the CII peptide fragments obtained after splitting the molecule by cyanogen bromide, the authors have demonstrated that the largest CII peptides (CB10 and CB11) were better recognized than the smaller peptides (CB8, CB9.7), with no significant difference between PR and control plasmas. Using competitive methods, evidence was obtained in support of heterogeneous recognition by the anti-CII antibodies: some recognize conformational determinants only, whereas others are targeted against the primary sequences of the alpha-1 (II) chain.

Antibody Diversity↗
PubMed1991

[Coronary spasm and diffuse coronary vasoconstriction responsible for transient left ventricular insufficiency].

A 52 year old patient presenting with spontaneous anginal chest pain for 4 days was admitted to hospital for a more intense and prolonged chest pain associated with signs of left ventricular failure (gallop, pulmonary crepitations, hypoxemia). Coronary angiography showed marked septal hypokinesia and spontaneous localised spasm of the left anterior descending and marginal arteries with a variable degree of luminal narrowing of the other segments of these two arteries and of the right coronary artery. These changes regressed after intracoronary injection of molsidomine. The signs of left ventricular failure disappeared in 48 hours. The wall motion abnormality, monitored by 2D echocardiography, regressed slowly over 3 days. On the other hand, the electrocardiogram, which showed anterior wall subendocardial ischaemia with prolongation of the QTc interval during the spasm, remained abnormal for a long time. Therefore, in the absence of organic heart disease, coronary spasms associated with vasoconstriction can induce a sufficiently severe and durable alteration of left ventricular function to create clinical signs of cardiac failure and profound and prolonged ST-T wave changes on the electrocardiogram.

Coronary Angiography↗
PubMed1990

T cell regulation of collagen-induced arthritis in mice. I. Isolation of Type II collagen-reactive T cell hybridomas with specific cytotoxic function.

After immunization with native type II collagen (CII), susceptible strains of mice (H-2q) develop a polyarthritis that mimics rheumatoid arthritis. Although the underlying mechanisms are still undefined, T cells and particularly CD4+ lymphocytes seem to play a crucial role in the initiation of collagen-induced arthritis. To investigate whether CD8+ cells may participate in the pathogenesis of the disease, we have generated lines and clones of cytotoxic T cell hybridomas reactive to CII by fusion of lymph node and spleen cells from bovine native CII-primed C3H.Q (H-2q) mice and the AKR-derived thymoma cell line BW 5147. Clones were selected for their ability to lyse syngeneic macrophages pulsed with bovine native CII in an Ag-dependent manner. The two hybrid clones that were characterized, exhibited cell surface phenotypes of cytotoxic cells and reacted with CII purified from various species. However, each of them recognized different determinants on the CII molecule. P3G8 clone was specific for an epitope shared by CII and type XI collagen, whereas P2D9 clone reacted with CII and type IX collagen. Both hybridomas recognized CII-pulsed targets in association with H-2Kq molecules. These data indicate that the two CII-specific cytotoxic clones recognize different epitopes that are shared by other articular collagens and will allow us to test their influence on the development of arthritis in vivo.

Animals↗
PubMed1990

Arthritogenicity of minor cartilage collagens (types IX and XI) in mice.

Native type II collagen, the major cartilage collagen, is immunogenic and arthritogenic in rodents. To investigate whether minor cartilage collagens are arthritogenic, we immunized DBA/1 mice with the pepsin-soluble fractions of type IX or type XI collagen emulsified in Freund's complete adjuvant. Both collagens were arthritogenic in DBA/1 mice after only 1 injection. However, the incidence of the polyarthritis was lower and the severity was lesser than with that induced by bovine type II collagen, even when a booster injection was administered. All mice developed a humoral response to the immunizing antigen, without any relationship to the arthritic status. Interestingly, competition experiments showed that antibodies raised against type XI collagen also bound with high avidity to type II collagen. In contrast, sera from type IX collagen-immunized mice did not react with either type II or type XI collagen. We conclude that types IX and XI minor cartilage collagens are both arthritogenic and immunogenic in DBA/1 mice. Whether the recognition of epitopes common to different collagens is relevant to the articular pathology remains to be elucidated.

Animals↗
PubMed1990

In vivo beneficial effects of cyclosporin A and 1,25-dihydroxyvitamin D3 on the induction of experimental autoimmune thyroiditis.

In a recent work, we provided evidence that the in vitro inhibitory effect of cyclosporin A (CsA) was potentiated by the addition of another immunosuppressive molecule, the 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). In the present study, we investigated the in vivo influence of the association of both drugs administered at infratherapeutic doses, using an experimental model of autoimmune thyroiditis in CBA mice. Treatment regimen of the animals was initiated at priming with thyroglobulin (Tg) and consisted of daily administration of CsA (10 and 20 mg/kg/day, intragastrically) and/or 1,25(OH)2D3 (0.1 and 0.2 microgram/kg/day, ip) for 21 days. Control mice that were given a placebo preparation orally and the vehicle of vitamin D3 metabolite ip developed a severe disease as assessed by histological examination on Day 28 postimmunization and detection of circulating anti-Tg antibodies. Treatment with either drug administered alone at the doses mentioned above did not affect the incidence of thyroiditis and only reduced by up to 26% the severity of histological lesions. In contrast, the mice treated simultaneously with both drugs exhibited a lower incidence of thyroid pathology and developed a significantly milder disease (P less than 0.001) as compared to controls. However, there was no alteration in the levels of anti-Tg antibodies. This in vivo beneficial effect of low doses of CsA and 1,25(OH)2D3 was not due to an accumulation of CsA in the blood of treated mice since the levels of CsA were similar, regardless of the administration of 1,25(OH)2D3. Our data suggest that these two immunomodulatory agents used together at low doses may be an effective therapy of autoimmune disorders with fewer side effects.

Animals↗