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R Zouari

Publications and source records attributed to R Zouari.

At least 19 recordsLinked to original sources
PubMed1993

Effect of sperm-associated antibodies on human sperm ability to bind to zona pellucida and to penetrate zona-free hamster oocytes.

Antibodies directed against sperm membrane antigens located mainly over the sperm heads were eluted from the sperm cell fraction of autoimmune ejaculates and transferred to antibody-negative spermatozoa of fertile donors. The ability of these antibody-coated spermatozoa to bind to the human zona pellucida and to penetrate zona-free hamster oocytes was evaluated in vitro. The majority of the sperm-eluted samples contained both IgA and IgG antibodies. In order to evaluate the effect of each class of antibody on the analyzed sperm functions, each isotype was specifically absorbed before transfer. Sperm-binding to salt-stored zona pellucida, as assayed by FITC and TRITC labeling of antibody-free and antibody-coated spermatozoa incubated with the same zona, was consistently reduced by 60-85% by the five eluted samples tested. Removal of either IgA or IgG antibodies from the eluted samples did not change the overall effect. Sperm penetration of zona-free hamster eggs was variously affected by sperm-associated antibodies. Of the 8 samples of sperm-eluted antibodies tested, only 4 had a significant effect on sperm penetration. Three of them decreased the penetration by 67-78%, while the fourth exhibited a modest increasing effect of 39%. These four samples contained antibodies of the two isotypes. In the samples with a decreasing effect, the elimination of one or another of the two isotypes restored the ability of the sperm to penetrate the hamster oocytes. These results suggest that sperm-associated antibodies may have different effects on zona-binding and gametic fusion events that lead to fertilization. Whereas IgA and IgG antibodies taken together or separately decreased sperm binding to the human zona pellucida, the two classes of antibodies must be associated in order to impair sperm penetration into zona-free hamster oocytes.

Animals↗
PubMed1993

Localization of antibodies on spermatozoa and sperm movement characteristics are good predictors of in vitro fertilization success in cases of male autoimmune infertility.

OBJECTIVE: To define sperm factors related to in vitro fertilization (IVF) failure in cases of antisperm autoimmunity. DESIGN: A detailed analysis of sperm morphology, movement characteristics, acrosomal function, and antibody binding was performed on the sperm population selected on a discontinuous two-layer Percoll gradient and used for IVF. The results were compared retrospectively between fertilizing (n = 13) and nonfertilizing (n = 11) sperm populations. PATIENTS: Twenty-one infertile couples undergoing 24 cycles of IVF treatment because of antisperm autoimmunity were included in this study. RESULTS: Fertilizing and nonfertilizing sperm populations were not different with respect to the percentage of motility, the normal morphology, the multiple anomalies index, the acrosome abnormalities, and the spontaneous or induced acrosome reaction. If the proportion of spermatozoa coated with either immunoglobulin (Ig)A or IgG antibodies was similar in the two groups, their localization was often different: antibodies were mainly on the sperm heads in the cases of fertilization failure. There were significant differences between fertilizing and nonfertilizing sperm samples in several movement parameters. Among them, the amplitude of lateral head displacement (ALH) was the most significantly correlated with fertilization success. Finally, spermatozoa were poorly bound to the zona pellucida (ZP) when fertilization failed, whereas high numbers of spermatozoa were attached to the ZP when fertilization occurred. CONCLUSION: Fertilization failure in patients with antisperm antibodies may be the result of several factors in which the impact of the antibodies on the membrane function play a critical role. Movement parameters, particularly the ALH and the localization of antibodies on migrated spermatozoa could predict the IVF failure or success more accurately than the proportion of antibody-coated spermatozoa in the inseminated populations. The fertilization failure was associated with an incapacity of spermatozoa to bind to ZP.

Acrosome↗
PubMed1992

Effect of sperm-associated antibodies on the dynamics of sperm movement and on the acrosome reaction of human spermatozoa.

Anti-sperm antibodies were eluted from the sperm cell fraction of autoimmune human ejaculates and transferred onto normal motile spermatozoa. The movement and the acrosomal status of these antibody-coated spermatozoa were evaluated after incubation in a capacitating medium. The amplitude of lateral head displacement (ALH) and the straight line velocity (VSL) were analyzed using an HTM automated motility analyser. Acrosomal loss was monitored by an FITC-conjugated lectin binding technique. During the 6-h incubation in BWW-BSA medium, antibody-free and antibody-coated spermatozoa exhibited significant changes of ALH and VSL distribution that evolved differently in the two populations. The dynamics of sperm movement in control spermatozoa were apparently modified by the presence of antibodies on the sperm membrane. The low percentage of spontaneous acrosomal loss obtained in control populations, even after 20 h of incubation, was not modified by the presence of antibodies on spermatozoa. However, the same antibodies decreased the acrosomal loss induced by a calcium ionophore after 3 h of incubation in capacitating conditions. These results suggest that sperm capacitation and acrosome reaction, considered as essential for successful fertilization, can be altered by antisperm antibodies present on human ejaculated spermatozoa.

Acrosome↗
PubMed1992

[Cervicobulbar intramedullary lipoma. Apropos of a case with review of the literature].

The authors report a case of cervical intramedullary lipoma extending into the bulbomedullary junction. 99 cases of cervical and/or dorsal intramedullary lipomas without spinal dysraphism, reported since 1884, are reviewed. There is poor correlation between lipoma's length and age of onset. Only lipoma extended to all the spinal cord begin in the first years of life. Clinical presentation is in 58% of cases a slowly compressive myelopathy, a syringomyelic syndrome in 9.5% of cases, a Brown Sequard syndrome in 6.5% of cases or atypical clinical features in 26% of patients. Finding of a subcutaneous lipoma at the level of the lesion helps for diagnosis. C.T. scan and magnetic resonance imaging (M.R.I.) precise lipomatous constitution of the tumor, its limits and relations with neighbouring tissues. Surgery is necessary when clinical features are advanced. Surgery indication is debatable when neurological manifestations are poor or absent. Post operative course is generally good and is not related with type of intervention.

Brain Neoplasms↗
PubMed1992

Bronchoalveolar lavage and transbronchial biopsy in spondyloarthropathies.

Fourteen patients (12 men, 2 women) with spondyloarthropathies underwent bronchoalveolar lavage (BAL), transbronchial biopsy (TBB) and other respiratory investigations. BAL revealed lymphocytosis and increased nonaltered neutrophil polynuclears in a smoker and an isolated lymphocytosis in one patient with restrictive syndrome and radiographic apical fibrosis. TBB showed interstitial fibrosis in the 2 patients and in 3 others who are all nonsmokers and among whom 2 had a restrictive syndrome. Subclinical alveolitis in spondyloarthropathies is absent. Interstitial fibrosis is not rare and its frequent association in a restrictive syndrome suggests a mechanical origin.

Adolescent↗
PubMed1991

In-vitro effects of anti-sperm antibodies on human sperm movement.

The present study was designed to investigate whether autoantibodies to external domains of the sperm plasma membrane affect the movement of normal motile spermatozoa. Eight sera and 20 seminal plasma samples containing high levels of anti-sperm antibodies as well as antibodies eluted from the sperm fraction of 19 autoimmune ejaculates were incubated with donor's motile spermatozoa, obtained by swim-up migration in Tyrode's solution. Sperm movement was analysed using 1 s exposure microphotography when greater than 70% of the spermatozoa were coated with antibodies (after 30-90 min of incubation). At least 50 tracks of progressively motile spermatozoa were analysed in order to obtain the mean values of the amplitude of lateral head displacement (ALH) and the velocity of progression (VSL). Serum antibodies and sperm eluted antibodies had quite consistent but opposite effects on sperm movement; serum antibodies increased ALH and decreased VSL whereas eluted antibodies decreased ALH and increased VSL. Seminal antibodies did not affect these two parameters significantly. Furthermore, seminal antibodies and sperm eluted antibodies obtained from the same ejaculates had distinct effects on ALH and/or VSL. This diversity was apparently not linked to antibody isotype or localization on the sperm membrane; it might be due to differences in the composition of the extracellular media. These results suggest a dynamic effect of anti-sperm antibodies on sperm movement, a possibility that merits further investigation.

Autoantibodies↗
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↗