PubMed Health⌕ Search

Biomedical subjects

K Ayed

Publications and source records attributed to K Ayed.

At least 19 recordsLinked to original sources
PubMed1992

Autoantibodies and circulating immune complexes in sera from patients with hepatitis B virus-related chronic liver disease.

Sera from 56 patients with hepatitis B virus-related chronic liver disease (CLD) and 30 normal individuals as controls were examined by enzyme immunoassay (EIA) for the presence of autoantibodies directed against actin, tubulin, myosin, double-stranded (ds) DNA, polymerized human albumin, thyroglobulin, and trinitrophenyl coupled to bovine serum albumin (TNP-BSA). Patients with CLD had consistently elevated levels of IgG, IgA, and IgM antibodies directed against all the panel antigens. The percentage of patients with autoantibodies of the IgA class was particularly high: respectively, 88 and 78% of the patients had strikingly high levels of anti-actin and anti-TNP-BSA IgA autoantibodies. High amounts of IgA and IgG antibodies to polymerized albumin as well as IgG to thyroglobulin were also detected. Circulating immune complexes (CIC) were isolated from patients' sera and their autoantibody activities were tested on the same antigen panel. The autoantibodies thus detected were of the same class and possessed the same activities, although at higher values than those present in the homologous sera. These results indicate that, regardless of their origin, autoantibodies are present in high amounts in the sera of these patients. Moreover, autoantibodies participating in the formation of CIC might play a pathological role.

Actins↗
PubMed1992

C4 polymorphism in multiplex families with insulin dependent diabetes in the Tunisian population: standard C4 typing methods and RFLP analysis.

The polymorphism of C4A and C4B genes was investigated in Tunisian patients with insulin dependent diabetes (IDDM) and compared to family members (sibs) and to healthy controls. Multiplex families were analysed. A significant increase in C4AQO (26.86% vs 6.90%) and C4BQO (40.29% vs 8.28%) phenotypes was noted in IDDM patients compared with controls. Using RFLP analysis, we confirmed the high frequency of C4 null alleles. We also observed that most of these alleles were genes deleted in IDDM patients (72.23% vs 20% for CA4QO and 74.07% vs 16.70% for C4BQO). A significant decrease in the C4B long (14.92% vs 67.12%) form of the gene was also demonstrated by RFLP analysis compared with controls. Two haplotypes were frequently associated with IDDM patients in whom the C4A and C4B were deleted genes.

Adolescent↗
PubMed1992

[Characterization and evolution of blood cryoglobulin in visceral leishmaniasis].

The evolution of immunological parameters in mediterranean visceral leishmaniasis reveal a type III mixed cryoglobulin with rhumatoid factor activity and antileishmania antibodies. This cryoglobulin follows the clinical signs of the disease and disappear under treatment. The authors insist on the transitory character of this cryoglobulin which is in relation with polyclonal stimulation of the immune system by parasitical infection.

Adult↗
PubMed1992

Abnormalities of T lymphocyte subsets in Behçet's disease demonstrated with anti-CD45RA and anti-CD29 monoclonal antibodies.

We assessed T cell subpopulations using 2-color flow cytometry with phycoerythrin conjugated anti-CD45RA and anti-CD29 and fluorescein conjugated anti-CD4 and anti-CD8 monoclonal antibodies, on peripheral blood lymphocytes from 19 patients with Behçet's disease (BD) and 18 healthy control subjects. The percentage of CD4+ cells was significantly lower in patients with BD (34 +/- 2%) than in control subjects (46 +/- 3%) (p less than 0.001). Among CD4+ cells, the percentage of suppressor-inducer (CD4+CD45RA+) cells was significantly lower in patients with BD (31 +/- 4%) than in control subjects (45 +/- 2%) (p less than 0.01), while the percentages of helper-inducer (CD4+CD29+) cells were similar in patients and controls. The percentage of CD8+ cells was significantly higher in patients with BD (36 +/- 2%) than in control subjects (26 +/- 2%) (p less than 0.001) involving both CD45RA+ and CD29+ subpopulations. Within CD4+ cells, the percentage of suppressor-inducer (CD4+CD45RA+) cells was significantly decreased in patients with active BD (26 +/- 3%) compared with control subjects (45 +/- 2%) (p less than 0.001), whereas in patients with inactive BD the difference was statistically insignificant. Our results suggest that the defective suppressive function in patients with active BD may be related to the decreased suppressor-inducer subpopulation (CD4+CD45RA+).

Adult↗
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↗
PubMed1991

Immunogenetic heterogeneity in type I (insulin-dependent) diabetes among the Tunisian population. HLA-DR antigens and organ-specific autoantibodies (family study).

The frequency of HLA-DR antigens, as well as the prevalence of islet cell insulin autoantibodies and other autoimmunity disorders, were investigated in Tunisian patients with insulin-dependent diabetes mellitus (IDDM) and were compared with family members (sibs) and healthy control subjects. Cytoplasmic islet cell autoantibodies (ICA) were found in 79 of 175 (45.1%) patients with IDDM, in 23 of 126 (18.25%) unaffected first degree relatives of type I diabetes patients and in only two of 146 (1.3%) control subjects. In 79 ICA positive patients with IDDM, 46.8% presented other evidence of autoimmunity by testing for specific autoantibodies. Insulin autoantibodies were found in 86.9% of healthy ICA-positive sibs. A good correlation between HLA-DR3/DR4 heterozygous phenotypes and the presence of ICA in patients with IDDM and their unaffected sibs was observed in the Tunisian population. In fact, this heterozygous phenotype is found in 63.3% of ICA-positive diabetic patients and in 44.4% of ICA-positive unaffected sibs, whereas, HLA-DR3/DR4 antigens were noted in only 22.9% of ICA-negative diabetic patients and in no ICA-negative unaffected sibs. In these studies, we also summarized the distribution of HLA-DR antigens in patients with IDDM who presented autoimmune disorders other than ICA.

Adolescent↗
PubMed1990

[Monoclonal gammopathies in Tunisia].

Protein electrophoresis and immunoelectrophoresis carried out on 4805 sera and 93 urine samples from Tunisian patients over 8 years, and a monoclonal protein was detected in 198 cases. The distribution of the monoclonal compounds to the clinical diagnosis was studied. 115 (58%) were classified as multiple myeloma (MK), 34 (17%) as alpha heavy chain disease (MCL a), 34 (17%) as monoclonal gammapathy associated to various diseases (GMOD), 11 (6%) as benign essential monoclonal gammapathies (GMBE), 4 (2%) as Waldenström's macroglobulinemia (MW). The relationship between the monoclonal immunoglobulin and the clinical diagnosis, the distribution of the monoclonal compounds according to the heavy chain class and the identification of the light chains were studied. The results obtained are in line with the principal data in literature concerning monoclonal gammapathy. However there is a particularity about monoclonal gammapathy observed in the Tunisian's population studied: Higher percentage of alpha heavy chain diseases, monoclonal IgD and monoclonal light chain. Lower percentage of monoclonal IgM in GMBE or GMOD, as in MW.

Aged↗
PubMed1990

Delta infection in chronic HBs Ag carriers in Tunisia: high prevalence in chronic asymptomatic HBs Ag carriers and in HBs Ag positive cirrhosis.

The presence of hepatitis B virus DNA, delta antigen and anti-delta antibodies was examined in 159 Tunisian chronic HBs Ag carriers: 45 were asymptomatic and 114 suffered from cirrhosis. Serum hepatitis B virus DNA was detected in two (4.5%) asymptomatic HBs Ag carriers and in 11 (10%) HBs Ag positive cirrhosis patients. The prevalence of HDV infection determined by the presence of anti-delta was relatively high in asymptomatic HBs Ag carriers (33%) and in HBs Ag positive cirrhosis patients (21%). Active ongoing HDV infection, detected by serum HD Ag and anti-delta IgM, was shown in five patients with cirrhosis and active hepatitis B virus replication. We conclude that hepatitis delta virus may be endemic in Tunisia and does not always inhibit hepatitis B virus replication.

DNA, Viral↗
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↗
PubMed1990

A new duplication C4B*1,12 at the C4B locus associated with BF*S07 in a Tunisian population.

Twenty-five Tunisian families were analyzed for their complement alleles in order to detect duplications at the C4 loci. In this population, the most characteristic duplications are C4A2, B1.12 or C4A1, B1,12 always associated with BFS07 and C2C. This previously undescribed C4B1,12 duplication was found in seven families, five times in association with HLA-A2, B50.

Alleles↗
PubMed1990

C3, BF and C4 polymorphisms in Tunisians.

The C3, BF, C4A and C4B polymorphisms were studied in a Tunisian population sample. The allelic frequencies for C3 were S = 0.844 and F = 0.148, and for BF, S = 0.535, F = 0.331, SO7 = 0.075 and F1 = 0.041. The most frequent C4 alleles were A3 and B1 followed in a decreasing order by A2, B2 and the A and B null alleles. The results indicate that the Tunisian population is intermediate between the Caucasian and Arab populations with some trace admixture of African Blacks.

Complement C3↗
PubMed1990

[The first thirty months of kidney transplantation in Tunisia].

Kidney transplantation is actually the best replacement therapy for the end stage renal failure. It sets free the hemodialysed patient from the hemodialysis restraint and contributes to solve the socio-economic problems risen by chronic hemodialysis. The authors report the results of this technic during the first 30 months of kidney transplantation in the "Hôpital Charles Nicolle" of Tunis. They describe the first steps which led to kidney transplantation, the therapeutic regimens, the medico-legal problems and the specific complications observed during this start period.

Costs and Cost Analysis↗