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Biomedical subjects

D Khayat

Publications and source records attributed to D Khayat.

At least 145 records · Page 8Linked to original sources

Role of infection in the modulation of mouse circulating soluble cell-free Fc gamma 2b/gamma 1 receptor.

We have recently demonstrated the occurrence of functional circulating soluble cell-free Fc gamma 2b/gamma 1 receptor in normal mouse serum by means of the 2.4G2 rat monoclonal antibody. With the solid phase radioimmunoassay described previously, we report here a dramatic increase in the level of circulating soluble cell-free Fc gamma 2b/gamma 1R in Schistosoma mansoni-infected mice individually tested before and on days 22, 41, 62, and 82 after infection. This increase was statistically highly significant when the five measurements from each mouse were compared, and also when the entire group of infected mice was compared with the stable level of Cf-Fc gamma 2b/gamma 1R measured in strain-, sex-, and age-matched control mice individually tested on the same days. This increase was commensurate with a rise in the amount of IgG detected in the sera of the S. mansoni-infected mice. Thus, infection seems to be one of the factors that modulate the expression of such soluble Cf-Fc gamma 2b/gamma 1R in mouse serum. Furthermore, the experimental device reported here for the production of high levels of Cf-Fc gamma 2b/gamma 1R by infection (in this case by parasitic infection) could serve as a model for obtaining large quantities of serum Cf-Fc gamma 2b/gamma 1R for further purification. Lastly, we point out that, by establishing a functional relationship with circulating IgG, such soluble Cf-Fc gamma 2b/gamma 1R may modulate some of the functions in which the Fc portion of immunoglobulins is involved.

Animals↗

Neoadjuvant chemotherapy of breast cancer.

About 80% of patients with breast cancer ultimately die of metastatic disease at 20 years. Distant metastases are more important as a cause of death than local or regional relapses. It is for this reason that adjuvant chemotherapy is necessary, especially in young patients and those with extensive disease. Initial chemotherapy preceding any local or regional treatment is justified on the grounds that both surgery and anaesthesia lead to immunodepression. Further, the value of initial chemotherapy has been demonstrated in many experimental and clinical trials by Nissen-Meyer, Bonadonna and Cooper (1-3). In the present study 145 patients, including 67 with inflammatory breast cancer (IBC), were treated with 4-6 weeks of Velbe, thiotepa, methotrexate, fluorouracil and prednisone, with Adriblastin added for patients with IBC, T greater than 7 cm, or N2, N3. Because of tumour regression of greater than 50% observed in 80% of the patients, the majority (123 patients) then received radiotherapy alone (cobalt + iridium), resulting in complete remission in all these cases. Maintenance treatment with the same drugs was prescribed for 6-18 months depending on the initial stage. Tumour regression appears to be an important prognostic factor. Median follow-up is only 17 months, the longest being 42 months. Overall survival at 2 years for IBC is 90%, with a disease-free survival of 80%. Cosmetic results are excellent. While these results are encouraging, longer follow-up is needed to confirm this improvement.

Antineoplastic Combined Chemotherapy Protocols↗

Prospective study of the potentiation of acenocoumarol by amiodarone.

The influence of oral amiodarone on the anticoagulant effect of the coumarin derivative acenocoumarol has been investigated prospectively in 10 patients with normal renal, hepatic and haematological function and who were not in cardiac failure. The daily dose of acenocoumarol was sufficient to produce a prothrombin activity of 25 to 35%. When the prothrombin time had become stable amiodarone 600 mg/d was administered for 1 week followed by 400 mg/d for the next 3 weeks. A decrease in prothrombin activity from 30.5 to 20.2% was observed, associated with a decrease in vitamin K coagulation factors, after a mean of 4 days following commencement of amiodarone. In 6 patients a prothrombin activity less than 20% required a 60% reduction in the dose of acenocoumarol after 1 week of amiodarone 600 mg, and a 33% reduction after 3 weeks of amiodarone 400 mg. There was no correlation between the plasma amiodarone and the decrease in prothrombin activity. Inhibition of acenocoumarol metabolism by amiodarone is the most likely explanation of these findings.

Acenocoumarol↗

[Role of azlocillin in the treatment of immunocompromised patients. Results of the EORTC (European Organization for Research on the Treatment of Cancer) study)].

A multicentre clinical trial was organized by the International Antimicrobial Therapy Project Groups of the European Organisation for Research on the Treatment of Cancer (E.O.R.T.C.) to compare the effectiveness of three combinations of antibiotics (azlocillin + amikacin; cefotaxime + amikacin and ticarcillin + amikacin) in patients with malignant leukopenic and febrile diseases (polymorphonuclears less than 1000/mm3; temperature greater than 38.5 degrees C). Some 800 patients from 20 centres entered the study. Preliminary results in 421 assessable patients showed a 62% positive response rate. The response rate in patients with bacteraemia was twice as high in the azlocillin group than in the other groups, the difference being significant at p less than 0.02. This difference does not seem to be due to a distribution bias, since the responsible micro-organisms, the severity of granulopenia, the incidence of bacterial-resistant strains, etc., were similar in all three groups. Similarly, the death rate was 12% in the azlocillin-amikacin group as against 15% and 17% respectively in the other groups. It would appear from this trial that the azlocillin-aminoglycoside treatment is superior to the other antibiotic combinations tested in this category of patients.

Agranulocytosis↗

Non-Hodgkin's lymphoma occurring after Hodgkin's disease. Four new cases and a review of the literature.

This article describes four cases of non-Hodgkin's lymphomas occurring after successful treatment of Hodgkin's disease (HD). The clinical symptoms consisted of digestive disorders, and the histology confirmed an intestinal involvement in these four patients. In all cases patients had diffuse large cell types (intermediate or high grade). The respective role of HD treatment (combination chemotherapy in 3 of 4 patients with irradiation in 3 of 4 patients) and of other pathogenic hypotheses, are discussed.

Adolescent↗

Circulating cellfree Fc gamma 2b/gamma 1 receptor in normal mouse serum: its detection and specificity.

By using intact or Fab fragments of rat monoclonal antibodies against murine Fc gamma 2b/gamma 1 receptor, in a solid phase radioimmunoassay, we demonstrated the occurrence of circulating cellfree Fc gamma 2b/gamma 1 receptors (Cf-Fc gamma 2b/gamma 1R) in normal mouse serum. These Cf-Fc gamma 2b/gamma 1R were removed from serum by affinity chromatography by using Sepharose columns coupled with IgG but not by Sepharose coupled with F(ab')2 fragments. Furthermore, the material retained by and eluted from the Sepharose IgG column reacted with the monoclonal antibody; these results support a direct relationship between the antigenic and the functional Cf-Fc gamma 2b/gamma 1R that were detected in serum. This Cf-Fc gamma 2b/gamma 1R was found in all the 39 normal mouse sera that were tested. The results seemed to indicate that aging may be associated with increased levels of Cf-Fc gamma 2b/gamma 1R and that levels of circulating Fc gamma R may be under genetic regulation. By forming complexes with circulating IgG within the blood stream, such Cf-Fc gamma 2b/gamma 1R may modulate some of the functions in which the Fc portion of Ig is involved.

Aging↗

[Robinow's syndrome].

Clinical and radiologic findings and differential diagnosis of the rare Robinow's syndrome are discussed in relation to one case. Features included nanism associated with multiple malformations such as mesomelic brachymelia, buccofacial anomalies, genital hypoplasia and hemivertebra. Transmission mechanisms are unknown and the karyotype is always normal.

Abnormalities, Multiple↗

[Robinow's syndrome. Apropos of a case with thrombopenia].

We report on a 17 month-old boy with Robinow' syndrome characterized by mild dwarfism, brachymelia, frontal bossing, hypertelorism, upturned nose, gingivodental, vertebral and bone age abnormalities, hypoplastic genitalia with normal gestation, birth weight and length and intelligence. There was an unusual association with idiopathic thrombocytopenic purpura and splenomegaly.

Abnormalities, Multiple↗

[Patient-centered consultation of "good practice guidelines": OncoDoc, a decision support system for the management of breast cancer patients].

Beyond considerations of cost-effectiveness, clinical practice guidelines (CPG) can reduce practice variations and thus improve the quality of care. However, despite the proliferation of implemented CPG and their wide diffusion thanks to Internet-based technologies, physicians' compliance with formal standards is weak. Developed according to a document-based paradigm, OncoDoc proposes an original framework for implementing CPG. Domain knowledge has been encoded as a decision tree whose branches are both exclusive and exhaustive. This generic knowledge is operationalized at the point of care by the interactive building, through hypertextual navigation, of a patient-based clinical context leading to specific therapeutic recommendations. OncoDoc has first been applied to the management of breast cancer patients and demonstrated within a full-scale experimentation in a clinical setting a compliance of 80 per cent.

Breast Neoplasms↗