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K Hamzaoui

Publications and source records attributed to K Hamzaoui.

At least 37 records · Page 2Linked to original sources
PubMed1992

[Pseudo-tumoral osteomyelitis. Immunologic study and etiopathogenic approach. Apropos of 2 cases].

Two cases of pseudo-tumoral osteomyelitis are reported. The first concerns a 12 year-old boy who presented with pain of the left knee during 8 months and, later on, with swelling of the upper extremity of the left leg, without fever or local inflammatory signs. The radiological aspect of condensation with a filling defect and "chimney" crossing the cartilage led to osteotomy. Local bacteriological samplings were normal. The second case concerns a 11 year-old boy who, after having complained from pain of the right wrist during 2 weeks, presented with swelling and on X-ray films a picture of metaphyso-epiphyseal lysis and an aspect of sequestrum in its center. There was no biological sign of inflammation. Evolution was favorable after antibiotic treatment and immobilization. In both cases, an immunological study showed an activation syndrome of the immune system with increased serum IL-1, IL-2 receptors and class II antigen receptors on the surface of T cells, suggesting a previous immunization of both children towards staphylococcus and, thereby, the subacute nature of evolution.

Child↗
PubMed1990

Natural killer cell activity, interferon-gamma and antibodies to herpes viruses in patients with Behçet's disease.

Interferon-gamma (IFN-gamma) titres in 20 patients with active Behçet's disease were examined and compared with those of 20 normal donors. Sera from Behçet's disease patients revealed an IFN-gamma increase but no correlation between IFN level and natural killer (NK) activity. The analysis of lymphocyte subsets by monoclonal antibodies registered an increase of CD8+ T subpopulation and cells co-expressing CD8(+)-Leu7a+ markers. Moreover, a high number of cells expressing CD25+ and HLA-DR+ phenotype has been noted in patients with active Behçet's disease. Serological analysis showed a high level of IgG antibodies to HSV-1. The increase of IFN-gamma titre, the high number of activated T cells and the increasing level of IgG antibodies to HSV-1 are important manifestations during the active stage of Behçet's disease. These findings are discussed in relation to the immunopathogenesis of Behçet's disease.

Adolescent↗
PubMed1990

Cytotoxic T cells against herpes simplex virus in Behçet's disease.

Lymphocytes from 36 patients with Behçet's disease (20 in remission and 16 in active phase) were stimulated in vitro with herpes simplex virus and then tested for their ability to generate cytotoxic T cell responses to the virus. Significant cytotoxic responses were found. CD4+ and CD8+ subpopulations from the patients in remission generated specific cytotoxic activity against autologous target cells. These observations suggested that CD4+ and CD8+ cytotoxic T cells may have an important host response in herpes virus infection in Behçet's disease.

Adolescent↗
PubMed1988

[Chronic proximal spinal amyotrophies in Tunisia. Clinical, genetic, epidemiologic and histopathologic study].

The results of a clinical, pathological, genetic and epidemiological study of 101 cases of chronic proximal spinal muscular atrophy are reported. Ages at onset allow to distinguish clearly an infantile, a juvenile and an adult groups. The infantile and juvenile groups comprising 93 p. 100 of the patients, were characterized by onset before the age of 20 (54 p. 100 before age 5) and by a large intra- and interfamilial clinical variability. The severity of the disease was unrelated either to sex or the sporadic or familial nature of the disease. On the other hand it was closely related to age at onset and to the pathology of the muscles. There seems to be no genetic heterogeneity in this group. Inheritance is of the autosomal recessive type in the great majority of cases. Certain sporadic cases may be due to a dominant mutation or to a phenocopy, as suggested by segregation analysis. The adult group, comprising 6 patients, included 4 cases of autosomal dominant inheritance without consanguinity of the parents, and one case of dominant inheritance.

Adolescent↗
PubMed1988

Natural killer cells in Behçet's disease.

We studied natural killer (NK) cell activity and numbers in the peripheral blood obtained from patients with Behçet's disease (BD) in inactive and convalescent stage, and from healthy controls. Ratios of helper/suppressor cells (OKT4/OKT8) were below 1.0 in patients with active stage and were normal in the convalescent stage of BD. A relative increase of OKT8+ cells and at the same time of Leu 7+ cells was obtained in the active and convalescent BD stages. Double marker analysis revealed that the sub-population of cells expressing both the T8+ and the Leu 7+ antigen (T8+/Leu 7+) was increased in patients with active stage, and normal in the convalescent stage. The frequency of cells reactive with Leu 11 monoclonal antibody (active NK cells) was evaluated in patients with BD. Data from peripheral blood showed an increased sub-population of T8+/Leu 7+ double marker cells, and a decreased Leu 11+ cell sub-population in patients with active BD, but the majority of Leu 7+ cells in patients with convalescent stage lacked OKT8 antigen when investigated in a double marker system. A parallel increase of Leu 11+ cells was observed in the convalescent stage. This phenotypic analysis was carried out with the NK in vitro functional evaluation of cell populations from peripheral blood. NK cell activity in the clinically active stage of BD was significantly lower than that of healthy controls and patients in the convalescent stage. The decrease of peripheral blood NK function in patients with active BD may be related to the presence of immature forms of NK cells and/or to the increased percentage of T8+/Leu 7+ cells.

Adult↗
PubMedDate not supplied

IL-18 mRNA expression and IFN-gamma induction in bronchoalveolar lavage from Behçet's disease.

OBJECTIVE: IL-18 expression and functional activity has been identified in several autoimmune and infectious diseases. To clarify the potential role of IL-18 during pulmonary Behçet's disease (BD), we have explored the capacity of IL-18 to induce the expression of IFN-gamma. METHODS: We studied bronchoalveolar lavage (BAL) from 12 patients with BD, 10 patients with silicosis as the control disease and 10 BAL from healthy subjects. BAL fluid, and BAL fluid cell cultures were investigated for IL-18 estimation by ELISA. Analysis of IL-18 and IFN-gamma gene expression was carried out before and after LPS stimulation. RESULTS: BD patients had significantly elevated levels of IL-18 in BAL fluid compared with control disease and healthy subjects. Induction of IFN-gamma and IL-18 were observed from BD-BAL fluid cells both spontaneously and after LPS stimulation, at higher levels compared to silicosis patients and healthy subjects (HC). Spontaneously only BD BAL cells expressed IL-18 mRNA and IFN-gamma mRNA. Forty-eight hours after LPS stimulation IL-18 mRNA and IFN-gamma mRNA were observed in BD, silicosis and HC cells. Recombinant IL-18 induced IFN-gamma production in BD- BAL fluid cells. CONCLUSION: Administration of IL-18 induced greater IFN-gamma production in BD-BAL fluid cells, than in normal BAL fluid cells. Our data indicate that IL-18 up-regulation is a feature of BD and suggest that IL-18 and IFN-gamma may contribute to the local inflammatory response in BD.

Adult↗
PubMedDate not supplied

Circulating soluble CD28 in patients with Behçet's disease: relationship to clinical manifestations.

OBJECTIVE: This study evaluates the presence of serum soluble CD28 (sCD28) in Behçet's disease (BD) and its relationship with clinical manifestations. METHODS: Soluble CD28 concentration was determined by ELISA in 120 patients with BD (80 patients in active stage), 60 patients with rheumatoid arthritis (RA) and 60 healthy subjects. RESULTS: Concentrations of sCD28 were significantly higher in patients with BD and RA than in healthy subjects. Patients with active BD expressed the highest level of sCD28 in serum. Soluble CD28 exhibited a drastic increase in active BD patients, compared to BD in remission. Soluble CD28 concentrations were higher in patients with active BD patients having vasculitis. Significant positive correlation was observed in a longitudinal study of 15 BD patients, between sCD28 and C-reactive protein. CONCLUSION: Our study suggests that fluctuations of sCD28 in BD reflects disease activity and should be assessed in evaluating disease activity.

Adult↗
PubMedDate not supplied

Suppressive T cell function of Epstein-Barr virus induced B cell activation in active Behçet's disease.

B and T cell function were studied in 10 patients with active Behçet's disease (BD) and in 10 normal subjects. Peripheral B lymphocytes infected with Epstein-Barr virus (EBV) were cultured for 20 days in the presence or absence of autologous T cells. Immunoglobulin M and G secretions into the supernatants were assessed with an enzyme-linked immunosorbent assay. The extent of suppression of EBV-induced B cell activation by autologous T cells was significantly decreased in active BD patients as compared to normal subjects at a T:B ratio of 1:1, whereas the suppression ratio was in the normal range at a T:B ratio of 4:1. The IgM and IgG secretions in purified B cell cultures were significantly higher in active BD patients as compared to control subjects. Thus, an increased B cell function associated with a defective EBV-specific T cell suppressive function could explain at least in part the immunological disorders in BD patients.

Adult↗