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S Boubaker

Publications and source records attributed to S Boubaker.

At least 19 recordsLinked to original sources
PubMed2006

Recombinant integrin CD11b A-domain blocks polymorphonuclear cells recruitment and protects against skeletal muscle inflammatory injury in the rat.

The beta2 integrin CD11b/CD18 (CR3) is a major adhesion receptor of neutrophils, normally utilized to fend off infections. This receptor contributes, however, to multiple forms of non-infectious inflammatory injury when dysregulated as shown in gene knock-outs and through the use of blocking monoclonal antibodies. The major ligand recognition site of CR3 has been mapped to the A-domain in the CD11b subunit (CD11bA). The recombinant form of this domain exhibits a ligand binding profile similar to that of the holoreceptor. To assess the potential anti-inflammatory activity of CD11bA as a competitive antagonist of CR3 in vivo, we assessed its effects on a developed animal model of traumatic skeletal muscle injury in the rat. Recombinant soluble rat CD11bA-domain fused to glutathione-S-transferase (GST) was administered intravenously in a single dose at 1 mg/kg to nine groups of Wistar rats, five in each group, 30 min before inducing traumatic skeletal muscle injury. Control animals received either a function-blocking anti-CD11b/CD18 monoclonal antibody (1 mg/kg), non-functional mutant forms of the CD11bA (D140GS/AGA, T209/A, D242/A), recombinant GST or buffer alone. In control animals, the wounded muscle showed oedema, erythrocyte extravasation and myonecrosis both within and outside the immediate wounded area (5-10 mm zone) and influx of neutrophils was detected 30 min post-wound, followed by a second wave 3 hr later. Wild-type CD11bA- or anti-CD11b monoclonal antibody (mAb)-treated rats showed a comparable and significant decrease in the number of infiltrating PMN (78 + 4%, n = 70 and 86 +/- 2%, n = 50, respectively) and preservation of the muscular fibres outside the immediate zone of necrosis (75 + 4%, n = 70, 84 +/- 1%, n = 50, respectively), compared to controls. These data demonstrate that CD11bA can be an effective tissue-preserving agent in acute inflammatory muscular injury.

Amino Acid Sequence↗
PubMed2006

Clinical and mutational investigations of tyrosinemia type II in Northern Tunisia: identification and structural characterization of two novel TAT mutations.

Tyrosinemia type II or Richner-Hanhart Syndrome (RHS) is an autosomal recessive disorder characterized by keratitis, palmoplantar keratosis, mental retardation, and elevated blood tyrosine levels. The disease is due to a deficiency of hepatic cytosolic tyrosine aminotransferase (TATc), an enzyme involved in the tyrosine catabolic pathway. Because of the high rate of consanguinity this disorder seems to be relatively common among the Arab and Mediterranean populations. RHS is characterized by inter and intrafamilial phenotypic variability. A large spectrum of mutations within TATc gene has been shown to be responsible for RHS. In the present study, we report the clinical features and the molecular investigation of RHS in three unrelated consanguineous Tunisian families including 7 patients with confirmed biochemical diagnosis of tyrosinemia type II. Mutation analyses were performed and two novel missense mutations were identified (C151Y) and (L273P) within exon 5 and exon 8, respectively. The 3D-structural characterization of these mutations provides evidence of defective folding of the mutant proteins, and likely alteration of the enzymatic activity. Phenotype variability was observed even among individuals sharing the same pathogenic mutation.

Adult↗
PubMed2005

[Colonic expression of gamma-interferon and interleukin-10 in Crohn's disease and ulcerative colitis].

OBJECTIVE: The aim of this study was to investigate mucosal expression of INF-gamma and IL-10 in patients with Crohn's disease (CD) or ulcerative colitis (UC). METHODS: Fourteen patients with CD and 11 patients with ulcerative colitis participated and 7 healthy subjects were also included. Study of the mucosal expression of INF-gamma and IL-10 was conducted using biopsies from healthy and damaged colons, using the inverse transcription and genetic amplification (RT-PCR) technique in real time (Taqman). Our results were expressed as ratio between messenger cytokine (mRNA) levels and ribosomal RNA level of a reference molecule (rRNA 18S), then multiplied by 108. RESULTS: In the cases of Crohn's disease, the mucosa expressed increased INF-gamma and IL-10 compared with controls (respective medians: 23.03 vs. 1.87 p=0.04 and 20.61 vs. 2.13 p=0.08). A strong positive correlation was found in the mucosal expression of IL-10 and INF-gamma during CD (r=0.9 p<0.0001). In contrast, in patients with UC, the expression of INF-gamma and IL-10 were comparable to those observed in the controls (7.18 vs. 2.18 p=0.36 and 3.66 vs. 1.87 p=0.44). CONCLUSION: During Crohn's disease, the expression of both IL-10 and INF-gamma was increased and strongly correlated, compared with the controls.

Adolescent↗
PubMed2005

[Lanthanides and microanalysis. Effects of oral administration of two lanthanides: ultrastructural and microanalytical study].

The subcellular localization of cerium and lanthanum in the intestinal mucosa was studied after oral administration of cerium chloride or lanthanum chloride or lanthanum chloride followed 30 minutes after of cerium chloride to young adults Wistar rats. Two methods of observation and microanalysis were used. The transmission electron microscopy revealed the presence of dense electron granulations in the lysosmes of the duodenum enterocyte, when these elements were administrated simultaneously. The ion mass microanalysis permits to detect the presence of La and Ce as bright points outlining the intestinal villi. These points correspond to the lysosomes containing the granulations previously described. These granulations are formed by the cerium and the lanthanum associated to the phosphor and forming probably insoluble salts of Ce/La phosphate.

Administration, Oral↗
PubMed2005

Chronic iodine overload and apoptosis in cold nodules from endemic multinodular goiters.

As apoptosis and necrosis are known to exist during experimental goiter development and involution, we studied them in ten Tunisian multinodular endemic goiters, five of them having received a chronic excess of iodine during six months. Apoptotic thyrocyte nuclei have been counted on hematoxylin-eosin stained semi-thin sections. Using immunoperoxidase on paraffin sections, bcl-2 and bax immunoreactivities have been evidenced, and CD34 positive microvessels counted; ultra-thin sections have also been observed. After six months of iodine overload, apoptotic thyrocytes were ten times more numerous; CD34 positive endothelial cells were diminished by one half bcl-2 immunoreactivity disappeared in thyrocytes and a bax one appeared in thyroid follicular and endothelial cells. Presence of numerous apoptotic follicular and endothelial cells was confirmed using electron microscopy. Chronic iodine excess induces apoptosis and necrosis of thyroid follicular and endothelial cells, leading to thyroglobulin accumulation in connective tissue.

Antigens, CD34↗
PubMed2003

A novel missense mutation in the gene encoding SLURP-1 in patients with Mal de Meleda from northern Tunisia.

BACKGROUND: Mal de Meleda (MDM) is a rare autosomal recessive skin disorder which belongs to the clinically and genetically heterogeneous group of palmoplantar keratodermas (PPK). Clinically, MDM is characterized by erythema and hyperkeratosis of the palms and soles with sharp demarcation that appears soon after birth and progressively extends to the dorsal surface of the hands and feet. OBJECTIVES: Except for the molecular study reported in Algerian families, MDM has not yet been investigated in the Maghrebian population, characterized by its heterogeneous ethnic background and a high rate of consanguinity. In this study we report genetic and molecular investigations of eight unrelated consanguineous Tunisian families including 17 affected individuals. METHODS: Eight large consanguineous MDM families who originated from cities of northern Tunisia, with a total of 17 patients and 22 unaffected family members were investigated. Families were genotyped with the following microsatellite markers: CNG003, D8S1751 and D8S1836. Mutation analyses were performed in affected patients, in both parents and in unaffected individuals. Linkage analysis was also performed. RESULTS: All the clinical features of MDM were constantly present. Nevertheless variable severity was noted among patients. Histological details were recorded. The haplotype analysis of markers CNG003, D8S1751 and D8S1836 revealed that all affected offspring were homozygous by descent for the three polymorphic markers. The maximum lod score value, 3.22, confirmed the evidence for linkage to the ARS gene. Three haplotypes were observed, and the findings suggest that at least three different mutations within the ARS gene segregate with these haplotypes. Three different mutations were identified, the 82delT mutation previously described and two novel missense mutations. CONCLUSIONS: The results suggest that the ARS gene is likely to be responsible for MDM in the eight Tunisian families. The clinical variability in the expression of PPK in MDM Tunisian patients might be accounted for by the intervention of modifier genes influencing the MDM phenotype.

Antigens, Ly↗
PubMed2002

[Bullous amyloidosis].

INTRODUCTION: The occurrence of skin damage during systemic amyloidosis is common, but the appearance of bullous lesions is rare. Only twenty-seven cases have been reported in the literature. We report our observation of bullous amyloidosis during progression of renal amyloidosis. OBSERVATION: A 61 year-old man, presented with white, soft, palpebral edemas of the lower limbs, without scutulum involvement, associated with a large cubital nerve that had appeared in March 1997. Biological explorations revealed a nephrotic syndrome. Pathologic study of the renal biopsy concluded in amyloidosis. Treatment with colchinine stabilized the renal damage. One year later, a non-pruriginous, papular and bullous eruption occurred, localized essentially in the axillary and inguinal-crural folds of the forearms and legs. In the presence of an amyloidal deposit and intra-epidermal detachment, the cutaneous biopsy was evocative of bullous amyloidosis. The search for concomitant myeloma was negative. Treatment with colchinine was effective. The bullous lesions disappeared after 2 months, and 21 months later, renal damage was still stable. DISCUSSION: These particularities in evolution are exceptional and have never been described. A hypothetical modification in the physico-chemical properties of the amyloidal protein might explain the bullous eruption and stabilization of renal damage.

Amyloidosis↗
PubMed2001

[Tracheopathia osteochondroplastica associated with a liver hydatic cyst broken in bronchi].

Tracheobronchopathia osteochondroplastica (TBOC) is an unusual respiratory disorder characterized by cartilaginous or bony mucosal nodules in the tracheobronchial tree. It mainly affects men over 50 years old and clinical manifestations are observed when obstructive or infectious complications occur. We report a case of tracheopathia osteoplastica of the upper third of the trachea in a young 35-year-old mal, fortuitously discovered while exploring a biliptysis caused by a broken hydatic cyst of the liver. TBOC can be associated with various metabolic, inflammatory and neoplastic disorders, but its pathogenesis remains unknown. A metaplastic origin is actually the main hypothesis proposed.

Adult↗
PubMed1999

[Bronchiectasis in a patient with ulcerative colitis].

Bronchopulmonary involvement is uncommon in ulcerative colitis. Bronchiectasis is a rare manifestation of the disease. We report a case of a 65-year-old patient with ulcerative colitis in whom we diagnosed bronchiectasis. The evidence of a relationship between bronchiectasis and ulcerative colitis was established on the basis of 3 criteria: the late occurrence of bronchiectasis in a patient without pulmonary history, their appearance after the ulcerative colitis developed and their improvement after inhaled corticosteroid treatment. This observation points out that ulcerative colitis investigations should be extended to the respiratory structures. The respiratory involvement is not always concomitant with the bowel disease. This observation suggests the efficiency of the inhaled corticosteroids in this disease.

Aged↗
PubMed1995

[Aggressive angiomyxoma of the perineum and pelvis. A report of two cases with pelvic and para-testicular localization].

Two cases of aggressive angiomyxoma of the pelvis and perineum are described; the first occurred in 32 year old woman who had a vulvar mass, the second in a 78 year old man who presented inguinal hernia. This recently described entity is characterized by its microscopic appearance (low cellularity, loose myxoid stroma and prominent vascular component), and propensity to local aggressivity, and common recurrence after surgery.

Adult↗
PubMed1994

[Collagenous enterocolitis. Apropos of a case and review of the literature].

Collagenous enterocolitis is a recent entity of which only two cases have been published. The authors report the association of collagenous colitis and collagenous sprue in a 67-year-old woman. The diagnosis of collagenous enterocolitis is based on the presence of a duodenal collagen deposit with partial villous atrophy associated with collagenous colitis. The symptom appeared one month after non-steroidal antiinflammatory treatment. The authors discuss the role of drug toxicity in the pathogenesis of collagenous enterocolitis.

Aged↗
PubMed1993

[Malignant rhabdoid tumor of the central nervous system. Apropos of a case with immunohistochemical and ultrastructural studies, and review of the literature].

The authors report a new case of cerebral malignant rhabdoid tumour in an eight year old girl. The diagnosis was confirmed on immunohistochemical and ultrastructural examinations showing cytoplasmic perinuclear inclusions composed of whorled filaments of vimentin. Base on a review of six cases reported in the literature, they analyse the clinical, histological, immunohistochemical and ultrastructural features of this exceptional central nervous system neoplasm. Different histogenetic hypotheses are discussed.

Brain Neoplasms↗