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R Bardi

Publications and source records attributed to R Bardi.

At least 19 recordsLinked to original sources
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↗
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↗
PubMed1991

[Familial form of gelatin drop corneal dystrophy].

We report 4 cases of gelatin drop dystrophy corneal amyloidosis in two brothers and two sisters of the same family. The age of onset is between 1 and 10 years. The corneal signs are described at different stages of development. Lesions are initially asymmetrical. The typical is a subepithelial nodule starting in the center and then expanding to involve the whole cornea. There is no relationship between extension and outcome of the disease. Diagnostic is confirmed by histological examination. There was no consanguinity between parents and no other cases were found in the family. An immunological study with HLA typing was performed. All patients were treated with lamellar or transfixing keratoplasty with a follow-up of 2 to 5 years.

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

[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↗
PubMed1989

[HLA, A, B, C, DR, C4, Bf in insulin-dependent diabetics in the Tunisian population].

There is no doubt that the autoimmune process in human disease depends on genetic factors. Varying associations were noticed between HLA DR and autoimmune disorders. The frequency of HLA-A-B and DR antigens as well as the Bf and C4 allotypes have been investigated in insulinodependant diabetes mellitus (IDDM) and compared to that of healthy controls in Tunisian population. An increase of A30, DR3, DR4, BfF1, C4AQ0 and C4BQ0 and decrease of B40, DR2, DR5 and DR6 were found in diabetes when compared to the value observation controls. The strongest association was noticed with HLA, DR3 and DR4. The prospective role of DR2 and DR5 antigens were also confirmed. Examination of HLA, Bf and C4 alleles. Two supratypes associated with IDDM have been observed among the Tunisian patients.

Adolescent↗
PubMed1988

[Complete deficiency in the C2 fraction of complement associated with a glomerular nephropathy: apropos of 2 cases].

Two patients with non-systemic idiopathic glomerulonephritis were found to have a complete deficiency of C2, the second component of complement; the clinical course and serological abnormalities are reported in detail. An immunogenetic analysis of the patients of two families was carried out. It was demonstrated that the homozygous C2 deficiency was associated with homozygosity for HLA-A25-B18-DR2-BfS-C4A4-C4B2 haplotype.

Adult↗
PubMed1987

HLA-A,B,C and DR antigens in a sample of the Tunisian population.

The HLA-A, B and DR phenotypes of 109 unrelated Tunisian individuals have been determined. The HLA-A and B antigen frequencies were compared with data reported for European Caucasoids and various Arab populations. Most similarities in antigen frequencies were seen between Tunisians and Kabyles from North Africa. A high frequency of HLA-A23 and HLA-Bw50 was observed in Tunisians and all Arab populations. A very close similarity in HLA-DR antigen frequencies exists between Tunisians and European Caucasoids. Linkage disequilibria between alleles of HLA loci were examined; many instances of previously reported antigen associations were seen in Tunisians, together with a number of associations which have not been described elsewhere. Aw34B8 and A2DRw14 are suggested as being common haplotypes in Tunisians.

Adult↗
PubMed1986

Solid state and solution conformation of Boc-L-Met-Aib-L-Phe-OMe. Beta-turn conformation of a sequence related to an active chemotactic peptide analog.

The conformation of the peptide Boc-L-Met-Aib-L-Phe-OMe has been studied in the solid state and solution by X-ray diffraction and 1H n.m.r., respectively. The peptide differs only in the N-terminal protecting group from the biologically active chemotactic peptide analog formyl-L-Met-Aib-L-Phe-OMe. The molecules adopt a type-II beta-turn in the solid state with Met and Aib as the corner residues (phi Met = -51.8 degrees, psi Met = 139.5 degrees, phi Aib = 58.1 degrees, psi Aib = 37.0 degrees). A single, weak 4----1 intramolecular hydrogen bond is observed between the Boc CO and Phe NH groups (N---O 3.25 A, N-H---O 128.4 degrees). 1H n.m.r. studies, using solvent and temperature dependencies of NH chemical shifts and paramagnetic radical induced line broadening of NH resonances, suggest that the Phe NH is solvent shielded in CDCl3 and (CD3)2SO. Nuclear Overhauser effects observed between Met C alpha H and Aib NH protons provide evidence of the occurrence of Met-Aib type-II beta-turns in these solvents.

Crystallization↗
PubMedDate not supplied

Association of type 1 diabetes mellitus with the HLA-DQA1*0301 allele in a Tunisian population.

HLA class II antigens are transmembrane glycosylated heterodimers composed of an alpha and a beta chain. Several of these chains are highly polymorphic. The structural bases of the polymorphism are nucleotide acid substitutions which are situated in the first domain (exon II) of alpha and beta genes. Specific sequences of these domains can be obtained by amplification of genomic DNA using the polymerase chain reaction. Polymorphic sites are recognized by restriction endonuclease treatment and separation of the DNA fragments by polyacrylamide gel electrophoresis. The resulting fragments of different lengths are used to identify different alleles. We used the above technique for typing the HLA-DQA1 alleles in 41 Tunisian diabetic patients. The frequency of DQA1*0301 was greatly increased compared with the control group. This was in agreement with previously published data in Caucasian and Japanese insulin-dependent diabetes mellitus (IDDM) patients, while the significant increase in the frequency of the DQA1*0501 allele was comparable with that of Caucasian IDDM patients but contrasted with a decrease in this allele in Japanese IDDM patients. Our results provide confirmation of the contribution of the DQA1*0301 allele to disease susceptibility in a Tunisian population.

Alleles↗
PubMedDate not supplied

Extended HLA haplotypes in multiplex families with insulin dependent diabetes mellitus in Tunisian population: HLA serological typing and RFLP analysis.

Haplotypes including HLA A, B, C, DR, and DQ were compared in a study population comprising 18 Tunisian multiplex families with diabetic children. Eighty haplotypes found in IDDM patients were compared with 148 haplotypes present in healthy family members. RFLP analysis showed that two DR subtypes were significantly more common in the diabetic haplotypes (DR4-DQw8: 82 per cent in IDDM members compared to 0 per cent in healthy members, p less than 0.001 and DR-Dw25: 56 per cent in IDDM patients compared to 16.7 per cent in healthy members, p less than 0.001) and these were in most cases found in haplotype combinations with HLA A2 B44 DR4 DRw53 and HLA A 24 B18 DR3 genes, respectively.

Diabetes Mellitus, Type 1↗
PubMedDate not supplied

HLA-antigens in a Tunisian familial chondrocalcinosis.

Thirty members of a Tunisian family with hereditary chondrocalcinosis were typed for HLA-A, B, and DR antigens: 7 affected and 23 unaffected subjects in three consecutive generations. The haplotype A1 B12 DR3 was found in all affected subjects and in 8 unaffected members. Chondrocalcinosis in this family may be associated with the haplotype A1 B12 DR3. The mode of transmission was autosomal dominant with incomplete penetrance.

Chondrocalcinosis↗