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Biomedical subjects

F Dreyfus

Publications and source records attributed to F Dreyfus.

At least 91 records · Page 5Linked to original sources
PubMed1995

Real time monitoring in the control theory paradigm.

Monitoring patients hospitalized in hemato-oncology departments to undergo clinical protocols of therapy is a complex task. The main difficulty arises in the follow-up of the oncology protocol and in the management of critical episodes of acute illness which frequently occur due to the high toxicity of the antimitotics used. This problem can be conceptualized within the control theory paradigm as the task of controlling a process whose state can deviate unacceptably from a normal range. Following the control theory analogy at the level of knowledge bases design, we have modeled the medical knowledge as control information to represent the medical actions, and state information is used as a feedback control to readjust the command.

Aged↗
PubMed1994

[Cost of intensive treatment followed by autograft of circulating stem cells. Application to multiple myeloma].

OBJECTIVES: Legitimate efforts to reduce health care costs, especially of intensive protocols including transplantation for haematological diseases, require realistic economic evaluations. We determined the direct cost of intensive chemotherapy associated with total body irradiation and autologous blood stem cell transplantation in patients with multiple myeloma. METHODS: Ten consecutive patients (7 males, 3 females) with Stage II or II multiple myeloma, who had received no prior treatment and were under the age of 55, were included in the study. Peripheral blood stem cells were collected by successive cytaphereses after a short period of aplasia induced by a CHOP protocol. During this period, the patients were in normal hospital rooms. A VAMP protocol was then administered in three 4-day sessions. Intensive therapy was started 1 month later with CCNU, etoposide, cyclophosphamide and melphalan. Total body irradiation (12 Gy) was performed on days -3, -2, -1. Autologous grafting was done on day 0. The intensive therapy was followed by a period of aplasia and the patients were protected in laminar flow rooms. Regular antibiotic and haematologic protocols were applied. Growth hormone was not given. The patients were seen regularly for follow-up and interferon alpha 2b was prescribed for 5. RESULTS: The mean cost of the two year treatment was 468,392 +/- 167,467 French francs. Personnel accounted for 36% of the total cost, marrow collection 13%, blood products 9.8%, laboratory tests 8.2% and drugs 7.2%. Little data are available in the literature of comparable cost analyses in other French hospitals or in other countries. CONCLUSION: Controlled cost/benefit studies should be conducted to enable a rigorous comparison between different therapeutic strategies.

Adult↗
PubMed1994

Acute-phase response, interleukin-6, and alteration of cyclosporine pharmacokinetics.

OBJECTIVE: Administration of interleukin-6 partially reproduces the inhibitory effects of the acute-phase response on cytochrome P450-dependent drug metabolism. The aim of the study was to determine whether endogenous cytokine has such an effect in patients treated by cyclosporine, which is metabolized by the cytochrome P4503A subfamily. METHODS: Blood cyclosporine and serum interleukin-6 levels were determined in six patients undergoing bone marrow transplantation, as long as they received cyclosporine by continuous infusion. Two serum acute-phase proteins, C-reactive protein and alpha 1-acid glycoprotein, and two cyclosporine metabolites, AM1 and AM9, were also determined. RESULTS: At the time of marrow infusion, levels of specific markers of inflammation were low. A peak in interleukin-6 level was then observed a mean of 10.8 days after transplantation, closely associated with variations in C-reactive protein levels. A parallel twofold increase in AM1 concentrations was observed, followed by a three-fold increase in cyclosporine levels, which peaked 4.8 days after interleukin-6. The times of peak cyclosporine and AM1 levels correlated with the time of peak interleukin-6 levels. AM9 was detectable in three patients but concentrations fell when interleukin 6 became detectable. CONCLUSIONS: An inflammatory reaction could be an important source of intraindividual variability in cyclosporine pharmacokinetics, possibly through an inhibition of cytochrome P4503A-dependent enzyme activities by endogenous interleukin-6. Blood AM1 accumulation might be explained by a secondary metabolic step that is highly sensitive to the inhibitory effect of interleukin-6.

Acute-Phase Reaction↗
PubMed1994

A spontaneous remission of lymphoid blast crisis in chronic myelogenous leukaemia following blood transfusion and infection.

We report a case of spontaneous remission of lymphoid blast crisis in chronic myelogenous leukaemia (CML) which returned to chronic phase, without the use of cytostatic chemotherapy, following an episode of viral infection and blood transfusion. Although complete remissions of acute leukaemia have been described, this evolution is extremely rare and has never been reported in CML blast crisis. The role of hypothetical factors leading to such a rare event are briefly discussed.

Aged↗
PubMed1994

[Paget disease, complicated by Ki-1 lymphoma with G-CSF growth factor secretion].

Development of lysis within an area of pagetic bone suggests a sarcoma. We report the case of a 61-year-old woman who had increasingly severe pain in her right hip and a decline in general health. The roentgenogram of the pelvis showed previously known pagetic lesions of the right half of the pelvis and osteolysis of the roof of the acetabulum. Additional imaging studies (ultrasonography, computed tomography, and magnetic resonance imaging) disclosed a pelvic tumor extending on either side of the right ilium. The peripheral white blood cell count was markedly elevated (93,000/mm3) as a result of inappropriate secretion of granulocyte-colony-stimulating factor. The tumor was an anaplastic large cell lymphoma of T-cell origin with CD30 positivity, i.e., a Ki-1 lymphoma. Most CD30-positive lymphomas are high-grade tumors. There has been only one previous report of Ki-1 lymphoma with production of granulocyte-colony-stimulating factor and hyperleukocytosis. It has been suggested that cytokines may influence tumor growth. Unusual features in our case include development of the Ki-1 lymphoma in an area of pagetic bone and presence of a leukemic syndrome due to increased production of a growth factor.

Bone Neoplasms↗
PubMed1994

[Treatment of mucositis with vitamin E during administration of neutropenic antineoplastic agents].

Mucositis represents one of the most frequent complications during chemotherapy or radiotherapy. Few studies have showed effective prevention against mucositis in this setting. In this randomized study, we tested the efficacy of vitamin E in the treatment of chemotherapy-induced mucositis. Twenty patients with malignant haemopathies were included; 19 patients were evaluable for the prevention of mucositis. Ten patients were treated with induction therapy for acute myelogenous leukaemia and 9 were treated with intensive therapy followed by autologous bone marrow transplantations. The severity of mucositis was evaluated according to World Health Organization classification. Our results showed that vitamin E may be of therapeutical value in the prevention of mucositis especially during induction therapy for acute myelogenous leukaemia.

Adolescent↗
PubMed1994

Pattern of expression of five alternative transcripts of the lck gene in different hematopoietic malignancies: correlation of the level of lck messenger RNA I B with the immature phenotype of the malignancy.

The lck gene encodes a tyrosine protein kinase of the src family which is highly expressed in T-lymphocytes. Two widely separated promoters govern expression of the lck gene. We report in this study that alternative splicing between cryptic donor and acceptor sites in the 5' untranslated region of the transcripts initiated at the type I promoter give rise to three different type I lck mRNAs, I A, I B, and I C. Altogether with the types II A and II B reported previously, the lck transcription is thus characterized by five alternative transcripts. We further used the complementary DNA-polymerase chain reaction assay to describe the pattern of expression of these five lck transcripts in different hematopoietic cell lines and in blood or bone marrow samples from healthy donors and leukemic patients. We report that the transcript II A is by far the major transcript present both in human samples and in T-cell lines. The low lck expression in B-cell lines is characterized by the quite exclusive presence of the transcript I B. We show that hematopoietic diseases characterized by the presence of immature cells [acute myeloid leukemia (AML-0 and AML-1) and T- and B-cell acute lymphoid leukemia] exhibit a marked increase of the transcript I B. No significant difference from the normal pattern is observed in AML according to the differentiation stage (AML-2 to AML-5). A normal pattern of lck expression is restored in AML-0 and AML-1 patients at complete remission.

Adolescent↗
PubMed1993

High-dose chemoradiotherapy and autologous blood stem cell transplantation in multiple myeloma: results of a phase II trial involving 63 patients.

Sixty-three patients with high tumor mass multiple myeloma were treated with high-dose chemotherapy and total body irradiation supported by autologous blood stem cell transplantation. After high-dose therapy, they were monitored for a median of 44 months. Seven patients died early from toxicity. All the other patients, including those whose disease was resistant to previous therapies, showed a tumor mass reduction. At 6 months postengraftment, 40 (71%) of the surviving patients had minimal residual disease and 11 (20%) were in apparent complete remission. During follow-up, 25 out of the 63 (39%) patients relapsed and 16 of these died; 31 (49%) had a sustained remission. The median overall and event-free survival times after transplantation were 59 and 43 months, respectively. The initial serum beta 2-microglobulin value (> or < 2.8 mg/L) and length of previous therapy (> or < 6 courses of chemotherapy) were the only significant prognostic factors. In all surviving patients, blood stem cell autograft provided satisfactory and sustained haematopoietic reconstitution most often within 15 days. High dose chemoradiotherapy followed by autologous blood stem cell transplantation is thus an important therapeutic option for young patients with aggressive multiple myeloma.

Adult↗
PubMed1993

Expression of the c-mpl proto-oncogene in human hematologic malignancies.

Similar to two other hematopoietic growth factor receptors, the c-fms (macrophage colony-stimulating factor receptor) and the c-kit genes, c-mpl has been discovered through the study of oncogenic retroviruses. Unlike c-fms and c-kit, which both belong to a subgroup of tyrosine kinase receptors, the c-mpl proto-oncogene encodes a new member of the cytokine receptor superfamily. We have studied the expression of c-mpl in a series of 105 patients with hematologic malignancies using Northern blot analysis. The levels of c-mpl transcripts in lymphoid malignancies and in chronic myeloproliferative disorders were not significantly different from those found in normal bone marrow cells, in which c-mpl was barely detectable. In contrast, c-mpl expression was increased in 26 of 51 patients with acute myeloblastic leukemia (AML) and in 5 of 16 patients with myelodysplastic syndromes. Amplification of the c-mpl gene was detected in genomic DNA of one M4 AML patient. There was no significant correlation between c-mpl expression and the French-American-British classification of AML. Patients with high c-mpl expression appeared to belong to a subgroup of AML with a low rate of complete remission and a poor prognosis, including secondary leukemia and AML with unfavorable cytogenetic abnormalities.

Acute Disease↗
PubMed1993

Cyclin A expression in human hematological malignancies: a new marker of cell proliferation.

Several in vitro studies have shown that the cyclin A gene is expressed and plays an important role in both the S and G2-M phases of the cell cycle. We analyzed cells from the blood and bone marrow of patients with various, mostly neoplastic, hematological disorders to determine whether (a) the cyclin A protein level correlated with that of cyclin A RNA and (b) cell distribution among the different phases of the cell cycle correlated with cyclin A RNA expression. Thirty-eight patients were studied by means of dot blot and Western blot techniques for cyclin A RNA and protein accumulation, and 21 were also studied for cell cycle distribution by using flow cytometric analysis. Semiquantitative studies were based on densitometric computerized evaluation of dot and Western blots. There was a very strong positive correlation between cyclin A RNA and protein expression (r = 0.99; P < 0.00005), indicating that cyclin A accumulation is regulated in these cells at a transcriptional level. There was also a highly significant positive correlation between cyclin A RNA expression and the cumulative percentage of cells in S plus G2-M phase (r = 0.98; P < 0.00005). Therefore, this in vivo study shows that the expression of cyclin A RNA and protein in human hematological malignancies correlates with the percentage of cells in S plus G2-M phase and identifies cyclin A as a new potential cell proliferation index in oncology.

Cell Cycle↗
PubMed1993

Contamination of peripheral blood by monoclonal B cells following treatment of multiple myeloma by high-dose chemotherapy.

Peripheral blood samples obtained from five patients with multiple myeloma, after high-dose chemotherapy, were studied for monoclonal B plasma cell contamination. We used the technique of immunoglobulin heavy chain gene 'fingerprinting' at the time of diagnosis and during apheresis. The level of sensitivity of this technique is between 0.01% and 0.001% in two patients in whom a monoclonal population was detected in peripheral blood.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Prognostic factors of invasive pulmonary aspergillosis in leukemic patients.

The study objective was to identify prognostic factors associated with survival in patients treated for acute leukemias who developed invasive aspergillosis (IA) during induction therapy. This retrospective analysis involved 21 patients treated in two hematologic centers over a six-year period. All were treated in protective isolated rooms with high-dose amphotericin B as soon as fungal infection was suspected. Ten (45%) of the twenty-one patients died. There was no statistical difference between the patients who survived and those who died in relation to the mean time of onset of IA or the total and mean daily dose of amphotericin B. On the other hand a favourable outcome correlated strongly with complete leukemic remission (p < 0.0001): all but one of the patients with objective residual leukemia died of IA, whereas all those who achieved complete hematological remission survived. In conclusion, it seems that the main vital prognostic factor in these leukemic patients with IA was the achievement of complete remission. We were unable to control IA in 10 of 11 patients with refractory leukemia, regardless of neutropenic status, despite early administration of high-dose amphotericin B. All the patients who achieved complete remission were successfully treated with amphotericin B.

Acute Disease↗
PubMed1993

Selective increase of alternatively spliced Lck transcripts from the proximal promotor in hematopoietic malignancies.

Screening by Northern blot for lck expression in 51 patients with diverse hematologic diseases has shown, for four of them, a 3 to 15-fold increase in the level of lck mRNA when compared with expression in healthy donors. These patients suffered from diverse malignancies: one Burkitt lymphoma, one T-cell lymphoma and two non-Hodgkin B-cell lymphoma. Specific analysis of the different lck transcripts in these patients by polymerase chain reaction and their relative quantitation demonstrate a significant increase of only the type IB and the type IC lck transcripts arising from the proximal promotor. Our study shows: (a) a high lck expression may occur in diverse hematologic diseases, (b) whatever the type of malignancy, this high expression results in a specific increase of the spliced transcripts arising only from the proximal promotor, and (c) in these four patients without any rearrangement or amplification, the high lck expression probably results from the specific activation of the proximal promotor.

Blotting, Northern↗
PubMed1992

Qualitative and quantitative analysis of human cytotoxic T-lymphocyte responses to HIV-1 proteins.

OBJECTIVE: To study the degree of immunogenicity of each HIV-1 protein. DESIGN: In most viral systems, antiviral cytotoxic T-lymphocytes (CTL) from a given donor preferentially recognize only one or a small number of viral proteins. METHODS: Anti-HIV CTL were generated by in vitro stimulation of peripheral blood mononuclear cells from seropositive donors and tested against multiple HIV-1 proteins or groups of proteins encoded by seven genes (env, gag, pol, nef, rev, tat and vif). Using autologous target cells infected with recombinant vaccinia viruses expressing one of the HIV-1LAI proteins, we compared the cytolytic activities obtained from bulk culture with those found in limiting dilution analysis (LDA). RESULTS: Our results were noteworthy for the following reasons. (1) Each responding donor reacted simultaneously to multiple proteins; this is very unusual in other viral systems. Anti-Gag CTL were detected in most, and anti-Pol in approximately three-quarters, of the patients, together with very high amounts of the corresponding CTL precursors in LDA. CTL against Env and Nef were found in two-thirds of the patients, while Vif- and Rev-specific CTL were less frequent. Finally, Tat was seldom recognized by CTL, but its antigenicity was revealed in LDA. (2) All responding cells revealed in bulk cultures as well as in LDA were CD8+ T-cells, and their in vitro differentiation did not require the help of CD4+ T-cells. (3) Proteins from the HIV-1LAI isolate were recognized with high frequency by CTL from seropositive donors, most certainly being infected by other isolates, which suggests that relatively conserved epitopes are predominant targets of CTL. CONCLUSION: Taken together, these results are encouraging for vaccine purposes, since anti-HIV-1 CTL stimulation is thought to be a requirement for such a vaccine.

AIDS Vaccines↗
PubMed1992

[Primary cutaneous lymphoma, with the exception of mycosis fungoides].

Cutaneous lymphomas other than mycosis fungoides (MF) form a rare and heterogeneous group. Their clinical behavior remains largely unknown. In this study, the clinical, immunohistological characteristics and follow-up data of 27 well-documented cases of primary cutaneous lymphomas other than MF, limited to the skin (stage IE) were reviewed. The tumors were divided into large-cell lymphomas (LCL) (21/27 = 77 p. 100) and small-cell lymphomas (SML) (6/27 = 23 p. 100). A B-cell phenotype was most often expressed by cutaneous lymphomas (23/27 = 85 p. 100). The clinical course of cutaneous lymphoma was closely dependent upon the histological subtype. Fourteen patients with LCL were treated by radiotherapy alone. Nine patients (64 p. 100) relapsed within two years post-treatment. Seven of them relapsed in the skin outside the initial site, suggesting that radiotherapy alone is not an adequate treatment for these patients. The preliminary results concerning 7 other patients with LCL treated with an initial third generation polychemotherapy regimen are presented.

Adult↗