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C Parmentier

Publications and source records attributed to C Parmentier.

At least 91 records · Page 5Linked to original sources
PubMed1990

Presence of mutations in all three ras genes in human thyroid tumors.

Polymerase chain reaction (PCR) amplification followed by oligonucleotide probing was used to investigate the presence of ras genes mutations in human thyroid adenomas and carcinomas. The results confirm the frequent occurrence of mutations in all three ras genes in both adenomas and carcinomas, in agreement with the hypothesis that the ras mutations may constitute early steps in thyroid tumorigenesis. No evident correlation between the frequency of ras mutations, the identity of the mutated ras gene, the position affected in the ras gene or the type of mutation and the pathological features is apparent. However, definitive conclusion on this point is precluded because of the small number of tumors examined at the present time.

Adenoma↗
PubMed1990

Inhibition of human bone marrow progenitors by the synthetic tetrapeptide AcSDKP.

The purpose of this work was to study the effects of a tetrapeptide, acetyl-N-Ser-Asp-Lys-Pro (AcSDKP), an inhibitor of spleen colony-forming unit (CFU-S) entry into DNA synthesis, on human progenitor cells. Normal human mononuclear cells were incubated with concentrations of the synthetic tetrapeptide ranging from 10(-12) to 10(-7) M for 1.5 and 24 h and then plated in methylcellulose in the presence of human placenta-conditioned medium and recombinant human erythropoietin. The proportion of progenitors in DNA synthesis was determined by the thymidine suicide assay. Incubation with AcSDKP for 24 h leads to a significant inhibition of granulocyte-macrophage colony-forming unit (CFU-GM) and erythroid burst-forming unit (BFU-E) growth and in some cases of erythroid colony-forming unit (CFU-E) growth. The inhibition, which was never greater than 50%, was obtained with 10(-10)-10(-9) M AcSDKP, whereas no effect was seen at higher concentrations. The percentage of CFU-GM, BFU-E, and CFU-E in DNA synthesis was significantly reduced in five consecutive patients after incubation of cells for 24 h with inhibitory doses of the peptide, indicating that it is active on cycling cells. Therefore, these studies provide the first evidence that the tetrapeptide AcSDKP, originally obtained from bovine marrow and now chemically synthesized, is able to inhibit the in vitro growth of human progenitors and to decrease their proportion in cell cycle.

Amino Acid Sequence↗
PubMed1989

[Riedel's thyroiditis. 3 cases].

Three cases of Riedel's thyroiditis are reported. The clinical presentation varied, with thyroid nodule in 2 cases (associated with cervical lymph node enlargement in 1 case) and compressive goitre with mediastinal involvement in the third case. The histological diagnosis of Riedel's thyroiditis is difficult and was made retrospectively in these 3 patients; it is based on the absence of malignant cells and the presence of fibrosis, inflammatory infiltrates and, inconstantly, vascular lesions of the occlusive phlebitis type.

Adrenal Cortex Hormones↗
PubMed1989

Value of venous catheterization and calcitonin studies in the treatment and management of clinically inapparent medullary thyroid carcinoma.

Seventeen patients with medullary thyroid carcinoma (MTC) underwent venous catheterization (VC) for sampling and serum calcitonin (CT) assay. The VC was performed either after an initial treatment in order to detect cervical recurrences and metastases (16 patients) or to prove abnormal CT thyroid secretion before any treatment (one patient). In 16 of the 32 tumoral localizations suspected by VC (50%), a tumoral focus was proven. For selective/peripheral CT gradient value superior to 2.50, 12 localizations of 12 (100%) were proven and for CT gradient value between 1.50 and 2.50, four localizations of 15 (26.6%) were proven. In six patients with exclusive cervical MTC secreting sites, treatment induced a total remission in two cases (12%) and improved in four cases (23%). The authors conclude that VC has a real value to localize MTC secreting sites. A total remission or an improvement can be obtained after treatment when VC detects exclusive cervical tumors.

Adolescent↗
PubMed1989

Hemoglobin Villejuif [beta 123(H1) Thr----Ile]: a new variant found in coincidence with polycythemia vera.

A new abnormal hemoglobin, Hb Villejuif [beta 123(H1) Thr----Ile] has been discovered during the exploration of a polycythemia in a 87-year-old patient of French origin. The isoelectric focusing of the lysate revealed the presence of a variant hemoglobin with an isoelectric point very close to that of HbA. The oxygen binding properties of the patient's red blood cells being normal, it was clear that the polycythemia was not a consequence of the presence of this hemoglobin. In fact, the red blood cell morphology and the involvement of the other blood cell lines, demonstrating excessive hemopoiesis, led to the diagnosis of polycythemia vera.

Aged↗
PubMed1989

Radiolabeled monoclonal antibodies against Reed-Sternberg cells for in vivo imaging of Hodgkin's disease by immunoscintigraphy.

The Hodgkin Reed-Sternberg (HRS-1) monoclonal antibody (Mab) was raised against the L 428 Hodgkin's disease (HD) cell line. The HRS-1 Mab was labeled with radioactive iodine and injected into six patients with Hodgkin's disease of varied histological subtypes for immunoscintigraphic imaging. In five patients, the HRS-1 Mab was labeled with 131I; a control anti-alpha-fetoprotein (AFP) Mab was injected simultaneously in two of these five cases. Four of five patients had a positive scan (nodal, splenic and hepatic involvements), the results in the fifth patient being equivocal. In the sixth patient, the HRS-1 Mab was labeled with 123I in order to utilize tomoscintigraphy instead of linear scintigraphy. Although the immunoscintigraphy (IS) was performed secondary to effective chemotherapy, images of bony disease were demonstrated. These preliminary results demonstrate that IS with iodine-labeled HRS-1 Mab is feasible and informative in Hodgkin's lymphoma. The real clinical value and the specificity of IS deserves confirmation in a larger series of patients. Several techniques such as the use of Fab or F(ab')2 fragments should further improve the results.

Adolescent↗
PubMed1989

The initial slope of human tumor cell survival curves: its modification by the oxic cell sensitizer beta-arabinofuranosyladenine.

The initial slope of the survival curve, which is a characteristic of each tumor cell line, varies with the histological group of the tumor. It is one of the factors on which clinical radioresponsiveness depends. The DNA dependant DNA polymerase inhibitor beta-ara A acts as an oxic cell sensitizer. This study was carried out on human tumor cell lines to look for a correlation between the degree of radiosensitization induced by beta-ara A and the radiosensitivity of a given cell line. Six human tumor cell lines with different radiosensitivities were used (the survival rate at 2 Gy and D ranged from 20 to 73% and from 1.2 to 3.2 Gy, respectively). beta-ara A had a major toxic effect on all cell lines but this varied greatly from one cell line to another and was concentration dependant; this toxic effect was taken into account when calculating the surviving fractions. For all cell lines, beta-ara A acted as an oxic radiosensitizer and the radiosensitization was concentration dependant. Analysis of the survival curves of the 6 cell lines using the linear quadratic model showed that concentrations of beta-ara A between 200 and 1000 microM induced an increase in the linear component while the quadratic component underwent no systematic change. The sensitizing enhancement ratio (SER) measured from the Ds ratios, varied greatly from one line to another. For example, at a concentration of 500 microM, the extreme values of Ds ratios were 1.5 and 2.6. The radiosensitization is greater, the higher the radiosensitivity of the cell line studied during exponential growth. The results do not favor the use of beta-ara A in the treatment of intrinsically radioresistant human tumors.

Cell Line↗
PubMed1989

Potential therapeutic role of cisplatinum in autologous bone marrow transplantation: in vitro eradication of neuroblastoma cells from bone marrow.

Cisplatinum may prove to be a valuable agent for the elimination of diseased cells in the bone marrow of patients with neuroblastoma. In this study, we measured the efficacy of cisplatinum on human neuroblastoma cell lines and on normal human bone marrow progenitors, GM-CFC and CFU-F. Data indicate that the therapeutic index of cisplatinum is high. We set up an experimental model consisting of a mixture of human bone marrow and human neuroblastoma cells in order to confirm these preliminary results in purging conditions. Results indicate that cisplatinum exhibits a high and specific tumoricidal property and appears to be valid in bone marrow purging.

Bone Marrow↗
PubMed1989

Comparison of sporadic and hereditary forms of medullary thyroid carcinoma.

Between 1960 and 1988, 185 patients with medullary thyroid carcinoma (MTC) were followed at the Institut Gustave Roussy in France. The screening of the family members by calcitonin measurement (basal or after pentagastrin stimulation) has led to the characterization of 38 sporadic cases and 44 hereditary cases. Among the hereditary cases are seven families with MTC only and two families with multiple endocrine neoplasia type 2A (MEN 2A). MTC only cases and MEN 2B cases are present as apparently sporadic forms. Hereditary cases consisted of 26 females and 18 males; the male:female ratio was 21:17 in sporadic cases. Ten of the sporadic patients were deceased (mean age 46 years) compared to three of the hereditary cases (mean age 59 years). The age at diagnosis was 44 years for the sporadic patients and 35 years for the hereditary MTC only patients with clinical manifestations. Histologic data from the sporadic and hereditary patients showed that the tumor is mostly unilateral without C-cell hyperplasia in sporadic cases and bilateral with C-cell hyperplasia in hereditary cases. The location of tumors was quite variable among the sporadic cases and mostly localized to the middle part of the thyroid lobes in the hereditary cases. Our data suggest that the age at diagnosis is later in sporadic forms of MTC and that the age at diagnosis is later in the hereditary forms of MTC only compared to those with MEN 2A.

Adult↗
PubMed1988

Autocrine differentiation-inhibiting factor (ADIF) from chicken erythroleukemia cells acts on human and mouse early BFU-E erythroid progenitors.

tsAEV-LSCC HD3 chicken erythroid cells transformed by the avian erythroblastosis virus (AEV) secrete an autocrine differentiation-inhibiting factor, ADIF, which blocks differentiation without affecting proliferation of the chicken erythroid cells that synthesize and secrete it into the culture medium. The chicken erythroleukemia cell ADIF activity is not restricted to avians. It prevents dimethylsulfoxide (DMSO) from stimulating murine Friend erythroleukemia cells to synthesize hemoglobin. ADIF also blocks erythroid differentiation in normal human and murine bone marrow where it selectively targets the early BFU-E (burst-forming) erythroid precursor cells without affecting the more advanced CFU-E erythroid precursor cells or cells of the different granulocyte-macrophage lineage.

Animals↗
PubMed1988

Construction and clinical validation of a sensitive and specific assay for serum mature calcitonin using monoclonal anti-peptide antibodies.

Using calcitonin (CT) as an hapten, we have generated a library of monoclonal antibodies. Six monoclonal antibodies were developed and analyzed with respect to affinity and specificity for epitopes on CT by enzyme linked immunosorbent assay and radioimmunoassay. These antibodies were used in the construction and the optimization of a two-site monoclonal immunoradiometric assay (m-IRMA) for CT. We used a combination of two monoclonal antibodies to develop an assay which is rapid (overnight incubation), sensitive (10 pg/ml) and strictly specific for the mature form of calcitonin, ie the 32 amino acid-long polypeptide bearing a prolineamide as the C-terminal residue. This assay was utilized to demonstrate that mature calcitonin circulates as heterogeneous molecular species resulting from polymerization of calcitonin by disulphide linkage and/or by aggregation on irrelevant proteins. The clinical relevance of this assay was studied on a series of patients with medullary carcinoma of the thyroid (MCT) and the characteristics of the assay was compared with those of a conventional polyclonal radioimmunoassay. The m-IRMA for CT proved to be useful for both the diagnosis and the follow-up of MCT.

Adult↗
PubMed1988

5-Fluorouracil, doxorubicin, and cisplatin regimen in adrenal cortical carcinoma.

Five patients with metastatic adrenal cortical carcinoma were treated with a combination of 5-fluorouracil (5-FU), doxorubicin, and cisplatin. All patients had a nonhormone producing tumor. A large tumor burden made them unsuitable for mitotane treatment. Treatment could be evaluated in four patients. A complete remission was achieved in one patient and lasted for 38 months: this patient is still alive and free of disease. Furthermore, a minor response and a disease stabilization also were observed. Cardiotoxicity occurred in one patient and myelosuppression in another patient. This regimen appears to be an active combination for the treatment of metastatic adrenal cortical carcinoma.

Adrenal Cortex Neoplasms↗
PubMed1988

[Management in cases of accidental contamination by iodine radioisotopes].

Iodide can reduce radioactive iodine thyroid uptake and whole-body irradiation. Maximal effectiveness is obtained when 3 conditions are fulfilled: adequate dosage: potassium iodide 130 mg (i.e. iodide 100 mg) as tablets in adults and older children, 50 mg in infants under one year of age; prompt administration after contamination and daily treatment as long as the contamination persists. Depending on the importance and duration of the contamination, different dosages may be required. In any case, children must be given priority for prophylactic measures.

Accidents↗
PubMed1988

Granulopoietic differentiation in long-term bone marrow cultures from children with congenital neutropenia.

The capacity of granulopoietic precursor cells (CFU-GM) to differentiate in vitro was evaluated in five children with congenital neutropenia using short-term colony assays and long-term marrow cultures. In all five children, methylcellulose assays revealed normal numbers of CFU-GM, which displayed an appropriate response to various sources of GM-CSF and differentiated up to the polymorphonuclear leukocyte state (PMN). In contrast, neutrophil PMN were not observed in long-term bone marrow cultures from three patients, despite a normal production of CFU-GM, myeloblasts, and promyelocytes during the 5-6 week culture period. Thus, in these patients, the characteristic "block" in granulocytic maturation observed in vivo was reproduced in vitro in long-term cultures. Granulocytic differentiation proceeded normally in long-term cultures from the two other patients, thus indicating heterogeneity in the expression of the defect. These results might indicate abnormal interactions between stromal and hematopoietic cells in long-term marrow cultures from some patients with congenital neutropenia. Furthermore, our results showed some correlation between the granulocytic defect in vitro and the clinical outcome in vivo.

Agranulocytosis↗
PubMed1988

Follow-up of patients with differentiated thyroid carcinoma. Experience at Institut Gustave-Roussy, Villejuif.

The recent introduction of sTSH assays allows for a definite control of the inhibition of TSH secretion. Clinical examination and serum thyroid hormone measurements are necessary to obviate hyperthyroidism. Relapses may occur after decades of apparent complete remission. Follow-up should be pursued throughout the patient's lifetime. Two specific means allow the detection of relapses at a stage when X-rays are still normal: measurement of serum thyroglobulin and 131I total body scan. Their combined use is recommended.

Follow-Up Studies↗
PubMed1988

Structure and expression of c-myc and c-fos proto-oncogenes in thyroid carcinomas.

Tumour specimens from 23 patients with thyroid carcinoma, 22 patients with thyroid adenoma, 3 with Graves' disease, and tissues from 8 normal thyroid glands were analyzed by Southern blot hybridization for the physical state of c-myc and c-fos proto-oncogenes. In 4 patients, both the primary tumour and lymph node metastases were analyzed. No amplification or rearrangement of the two proto-oncogenes was detected. Total RNAs were also analyzed. Elevated levels of the 2.4 kb c-myc RNA and of the 2.2 kb c-fos RNA were found in 13/23 (57%) and 14/23 (61%) of the cancer patients, respectively. High levels of c-myc transcripts were more frequently found in thyroid carcinomas with unfavourable prognosis. Concomitant elevated levels of both c-myc and c-fos RNAs were found in 8 cancers. High levels of c-myc RNA were also found in 1 out of 22 specimens of adenoma, in 1 specimen of Graves' disease and in 2 normal thyroid glands. High levels of c-fos RNA were found in 20 of the 22 adenoma samples and in 2 out of 8 normal thyroid tissues. These data indicate that the overexpression of c-myc and c-fos genes is independent of an alteration of the loci. The high levels of c-fos found in adenoma may be associated with the differentiation state of these tumours.

Adenoma↗