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Biomedical subjects

A Mazabraud

Publications and source records attributed to A Mazabraud.

At least 73 records · Page 4Linked to original sources
PubMed1982

[Value of the study of the kinetics of 85 strontium for the classification of osteogenic sarcomas ].

Because of the polymorphism of osteogenic sarcomas, examination of a biopsy specimen, which is necessarily small, cannot give an accurate evaluation of the differentiation of the whole tumor. Therefore, a test which provides an overall assessment of the functional capacity of the tumor is needed. For the last ten years, we have been using 85 strontium, which has a metabolism similar to that of calcium and radioactive characteristics that allow external measurements. With this isotope, classification of osteogenic sarcomas is more accurate, ensuring better therapeutic trials.

Adult↗
PubMed1982

[An experimental model of osteosarcomas in rats ].

Satisfactory experimental models for preclinical prediction in cancerology must answer the following criteria: reproducibility of the method used for inducing tumors; clinical, pathological and kinetic similarity with the corresponding human tumors. We have developed a model of osteosarcoma locally induced by insoluble radioactive cerium chloride (144Ce CI3) in Sprague Dawley rats. This method yields over 80% of bone tumors at the injection site, of which approximately half are histologically similar to human tumors. These tumors double their volume fairly slowly (in approximately 20 days); lung metastases occur both early and frequently (80% of animals). A transplantable tumor was developed from an induced osteosarcoma and adapted to the Curie strain. Transplantation in the bone, next to the bone, or under the skin is followed by widespread metastatic dissemination. The kinetics and histological features of the primary tumor are maintained. Tumor 85 strontium uptake is similar to that seen in human osteosarcomas. These new models of osteosarcomas are being used for evaluating new cancer chemotherapeutic agents and interferon, etc.

Animals↗
PubMed1982

Hemangioendothelioma (angiosarcoma) of bone: a distinct pathologic entity with an unpredictable course?

Eighteen cases of hemangioendothelioma (angiosarcoma) of the bone were found in a review of the files of the Department of Pathology of the Institut Curie. The ages of the patients, 11 males and seven females, ranged from 12--69 years (median 32 years). Pain was the usual symptom (11/16). Fifty percent (9/18) of the tumors occurred in the long tubular bones. Radiographic findings showed osteolytic, often multifocal, lesions without evidence of reactive bone formation. Grossly, the tumor masses were always found to be confined to the cavity of the bone. In all cases microscopic findings fulfilled the diagnostic criteria proposed by Stout. Solid and cellular small structures closely resembling embryonal vessels were observed in several instances, and were also helpful in identifying the endothelial vascular nature of the tumors. The histologic grade was difficult to determine in the majority of cases because there were several areas with different grades of differentiation. Of 15 patients with follow-up data, seven were alive and well with no evidence of disease 2--14 years after diagnosis (median nine years). Another patient was alive with metastatic disease after five years. The survival of the seven patients who died ranged from 7--53 months (median 21 months). This study confirms that hemangioendothelioma of the bone is a distinct pathologic entity. In contrast, it appears very difficult to determine the common clinical behavior of these tumors because they can show an extremely variable malignant potential.

Adolescent↗
PubMed1982

The nucleotide sequence of phenylalanine tRNA of Xenopus laevis.

The nucleotide sequence of Xenopus laevis phenylalanine tRNA extracted from oocytes was determined to be: pGCCGAAAUAm2GCUCm1AG DDGGGAGAGCm22 G psi psi AGACmUGmAAYA psi C UAAAGm7GDCm5CCUGGT psi CGm1AUCCCGG GUUUCGGCACCAoH. This result was achieved by analysing, with classical procedures [6], the oligonucleotides obtained after digestion by T1 or pancreatic ribonuclease. This sequence is identical to the mammalian sequence. It has been entirely conserved during 10(8) years, the time lapse between the divergence of amphibians and mammals in evolution. In contrast to 5S RNA, no important heterogeneity has been found in the oocyte sequence, suggesting that there is only a single sequence for tRNAphe in X. laevis. Small differences are seen in the elution pattern from RPC-5 columns for immature oocyte and somatic tRNAphe. They are probably due to a submodification of methyl-5-cytidine residues, which appear to be about half methylated in tRNAphe as well as in total tRNA from immature oocytes.

Animals↗
PubMed1981

Acute nonlymphocytic leukemias following chemotherapy. Ultrastructural study of erythroblastic cell line and discussion of nuclear anomalies.

In 18 cases of drug-induced acute leukemia, electron microscopy brought out a number of anomalies found in all hematopoietic cell lines. They are described here for the erythroblastic line. Some of these anomalies occur in the cytoplasm (like siderosomes, iron-containing mitochondria, glycogen spots, various dense inclusions, and nuclear-cytoplasmic asynchronism; others occur in the nucleus (such as plurinucleated cells, fragility of nuclear membrane, and nuclear clefts and blebs). Nuclear clefts and blebs may also be found in granulocytic and megakaryocytic cell lines. Their structural aspect suggests a relationship with chromosomal abnormalities, particularly with synaptonemal complexes. Unusual karyotypes, observed in two cases, give weight to such a hypothesis. The cell injury caused by alkylating agents, including DNA lesion, is most likely closely related to this particular pattern of drug-induced leukemias.

Alkylating Agents↗
PubMed1980

[Treatment of Ewing's sarcoma by radiotherapy and adjuvant chemotherapy : results at 3 and 5 years (author's transl)].

The local treatment of Ewing's sarcoma by radiotherapy is classically linked to a very poor prognosis : 10 to 15% of 5 years survival, 75 to 95% of distant metastasis in 2 years. The combination of local radiotherapy to a systemic adjuvant chemotherapy have been recently shown to give a real benefit to this prognosis. The therapeutic trial of the EORTC and GETO, presented here allows us to hope a disease free survival at 5 years for 50% of our patients and a complete survival at 5 years for 56% of them.

Antineoplastic Agents↗
PubMed1980

Acute myeloid leukemia following non-Hodgkin's lymphoma: danger of prolonged use of chlorambucil as maintenance therapy.

Four patients who developed acute myeloblastic leukemia during the treatment of a non-Hodgkin's lymphoma are described. In three cases the same sequence was observed: a favorable histological type of lymphoma, an apparently complete and lasting remission, a long period of tri-cytopenia, and finally acute myeloid leukemia. The fourth patient had a non-favourable histological type of lymphoma and developed acute myeloblastic leukemia during a relapse. The illustrations clearly show the distinction between lymphoid and myeloid disease in the four cases. A review of previously reported similar cases is summarized in two tables. Many patients received chemotherapy including alkylating agents (as did the four patients reported here). Most of them received chlorambucil, usually given over several years, at total doses ranging from 2 to 15 g. This treatment, frequently used as maintenance therapy in low-grade malignancy lymphoma, seems to be particularly dangerous.

Adult↗
PubMed1979

[Angioimmunoblastic lymphadenopathy: ultrastructural study of lymph nodes. Possible relationship with Epstein-Barr Virus (EBV) (author's transl)].

Angioimmunoblastic lymphadenopathy (AIL) has been clinically and histopathologically described by several authors since 1972, but only a few papers have analyzed the morphological aspects of the lymph nodes as observed by using electron microscopy. In the past three years, we happened to see in the Curie Institute two typical cases of AIL, both of whose clinical and immunological data are briefly reported in this paper. We describe some peculiar patterns observed on the lymph nodes during the acute phase of the disease, by examination of semithin sections and electron-microscopic preparations. As have many others, we found strong diffuse B-lymphocyte proliferation, but we must emphasize that many plasmocytes had an obvious defect in cell maturation, but no monomorphous defect. We noted that the predominant postcapillary venules had hypertrophied endothelial and perithelial cells, and multilayering basal lamina. We found some unusual features such as lymphocyte and/or plasmocyte phagocytosis by macrophages, or the atypical aspect of eosinophilic granulations. Finally, in the cytoplasm of a few transformed lymphocytes we detected some viral-like particles resembling herpes virus. Whether this last finding may have been related to the pathogeny of AIL could not be resolved by using morphological techniques. In the second part of this paper, we discuss the etiology of the disease, taking in account our clinical, immunological, and morphological observations. The possible relation of AIL to infectious mononucleosis, and the hypothetical role of Epstein-Barr virus are discussed.

Acute Disease↗
PubMed1979

[Maxillofacial radiation-induced cancers (author's transl)].

Radiation-induced cancers are fortunately a very rare complication of radiotherapy for cancers. Sagerman, however, reported 21 cases in a series of 243 patients with retinoblastomas, examined after a period of at least 5 years, and 6 cases were observed in a similar series of 112 children seen at the Curie Institute. This report describes 10 cases of irradiation-induced cancers of the maxillofacial region seen at the Curie Institute over a period of 30 years. The exceptional nature of this risk is such that it cannot represent a contra-indication to irradiation therapy of a malignant tumor, especially now that low-energy radiation has been abandoned, and with the modern therapeutic procedures available. The risks of cancer are greater, however, after irradiation of benign bone lesions and benign affections of the cervico-facial region. Treatment of these benign affections in children or young adults by low or reduced doses of conventional low-energy radiations should be forbidden, and the indication for treatment with radiations, which must be of high voltage, should be exceptional.

Adolescent↗
PubMed1979

Primary lymphomas of bone (so-called ("Parker and Jackson's reticulum cell sarcoma") : histological review of 75 cases according to the new classifications of non Hodgkin's lymphomas.

75 cases of primary lymphomas of bone ("reticulum cell sarcoma" described by Parker and Jackson) were reviewed. Biopsy specimens were classified according to several histological classifications, including Lukes' classification for nodal lymphomas. Among 24 tumors described as "histiocytic lymphomas" in Rappaport's classification of 1966, only one case remains as "true histiocytic sarcoma". The others were reclassified as follows : 6 tumors with a predominance of large cleaved cells, 13 tumors with large non-cleaved cells, 2 as immunoblastic tumors and 2 as unclassifiable. In non Hodgkin's lymphomas, the histological diagnosis and the results of the initial staging have been shown to be greater aids in the prediction of survival than the primary site of the disease. Therefore, the clinical and therapeutical approach to the patients with lymphomas of bone must be modified to be similar to that of patients with nodal localisations of the disease.

Adolescent↗
PubMed1978

[Clear-celled chondrosarcoma or chondroblastic sarcoma. A new type of chondrosarcoma (author's transl)].

The authors report five cases treated by wide resection. Pathological studies were made of the whole of the lesion. Three tumours were situated at the upper end of the femur, one at the upper end of the humerus and one at the level of the tibial plateau. The specific features were localisation in an epiphysis and histological areas of clear cells whose cytoplasm contained glycogen. From the anatomical and radiological points of view, these tumours were like chondroblastomata but their progress was more like that of chondrosarcomata. The author concludes that they should be distinguished from both types of tumour.

Adult↗