Congenital anomalies in Tunisia: Frequency and risk factors.

BACKGROUND: Despite the high risk of recurrence of congenital malformations, there are no well-accepted preventive measures in developing countries like Tunisia. It is recommended that thorough epidemiological studies of congenital anomalies in this country are needed. The aim of this study is to assess the frequency and types of congenital anomalies in Tunisia and research some risk factors associated with occurrence of these anomalies. METHODS: In this retrospective study, all the fetuses who were autopsied during 21years period from February 1991 to December 2011 (n=9678) at Service of embryofetopathology in the Center of Maternity and Neonatology of Tunis (CMNT) were studied. The classification of malformations was based upon the anatomical system affected. The differences in fetal/maternal characteristics between cases with or without congenital malformations were assessed using Chi2 test. RESULTS: Of the all 9678 autopsied fetuses, 4498 (46.47%) were diagnosed as being malformed fetuses. Anomalies of limbs (22.71%) and digestive and abdominal wall defects (14.76%) were mostly detected, followed by congenital brain defects (13.41%) and nephrourologic abnormalities (11.23%). A marked association of parental consanguinity with increased congenital anomalies rates was found (P<10-6, OR=1.89, CI=1.69-2.13). CONCLUSION: In Tunisia, surveillance and epidemiological evaluation of congenital anomalies underline the high frequency of these events. This will help to better target congenital anomalies prevention and screening policies in our population.

Circulating Cell-free miRNA Expression and its Association with Clinicopathologic Features in Inflammatory and Non- Inflammatory Breast Cancer.

Recent discovery showing the presence of microRNAs (miRNAs) in the circulation sparked interest in their use as potential biomarkers. Our previous studies showed the diagnostic potential of miR-451 as a serological marker for inflammatory breast cancer (IBC), miR-337- 5p and miR-30b for non-inflammatory breast cancer (non-IBC). The aim of this study is to investigate the prognostic values of circulating miRNAs by comparing the amounts of 12 circulating miRNAs in the serum of IBC and non-IBC from Tunisian breast cancer patients, and by determinating whether correlated pairs of miRNAs could provide useful information in the diagnosis of IBC and non-IBC patients. TaqMan qPCR was performed to detect circulating expression of miRNAs in serum of 20 IBC, 20 non-IBC and 20 healthy controls. Nonparametric rank Spearman rho correlation coefficient was used to examine the prognostic value of miRNAs and to assess the correlation profile between miRNAs expression. Further, a large number of miRNAs were highly correlated (rho>0.5) in both patients groups and controls. Also, the correlations profiles were different between IBC, non-IBC and healthy controls indicating important changes in molecular pathways in cancer cells. Our results showed that miR-335 was significantly overexpressed in premenopausal non-IBC patients; miR-24 was significantly overexpressed in non-IBC postmenopausal patients. Patients with previous parity had higher serum of miR-342-5p levels than those without. Furthermore, patients with HER2+ IBC present lower serum levels of miR-15a than patients with HER2- disease. Together, these results underline the potential of miRNAs to function as diagnostic and prognostic markers for IBC and non-IBC, with links to the menopausal state, Her2 status and parity.

[Psoriasis: physiopathology and immunogenetics]. / Le psoriasis: physiopathologie et immunogénétique.

Psoriasis is a multifactorial disease that involves genetic, immunological and environmental factors. During the last decade, several studies by genome scan on families or cases/controls helped to highlight more than ten loci "PSORS" located on different chromosomes and containing several candidate genes. Psoriasis appears as a genetic disease that follows the mixed model with the involvement of a major gene (PSORS1) and a set of minor genes with a variable penetrance depending on the locus. Genetic data have focused on the involvement of the immune system in the pathogenesis of psoriasis. It is now accepted that psoriasis is an immunological disease involving the response profiles TH1 and TH17. Much remains to be done to better elucidate the mechanisms involved in the genesis of psoriatic lesions to find new therapeutic targets.

Failure to find evidence for deletion of LCE3C and LCE3B genes at PSORS4 contributing to psoriasis susceptibility in Tunisian families.

BACKGROUND: Recently, it has been shown that a deletion in the late cornified envelope (LCE) gene cluster (LCE3C_LCE3B-del) is associated with susceptibility to psoriasis in European and Asian populations. However, no study of this deletion has been performed in the North African population. The aim of the present study was to investigate whether this deletion is associated with familial psoriasis in Tunisian population. METHODS: A total of 34 patients and 55 healthy individuals were recruited from 7 multiplex families and a PCR assay was used to determine the association of this deletion. Its effect on susceptibility to psoriasis was assessed using the PDT program. RESULTS: We failed to detect any evidence of association between LCE3C_LCE3B-del and psoriasis in Tunisian families. No epistasic effect was found between the deletion and PSORS1 locus. CONCLUSIONS: These findings indicate that the LCE3C_LCE3B-del does not contribute in a major way to psoriasis susceptibility in Tunisian families.

Genome-wide linkage scan for psoriasis susceptibility loci in multiplex Tunisian families.

BACKGROUND: Psoriasis is a relapsing chronic inflammatory skin disease affecting all population groups, with a peak prevalence of 3% in northern European and Scandinavian caucasians. Epidemiological studies have implicated a genetic component to psoriasis. In the past 12 years multiple genome-wide linkage analyses have identified putative susceptibility loci on several chromosomes, with a major locus in the major histocompatibility complex region. OBJECTIVES: To investigate the genetic basis of familial psoriasis in the Tunisian population using a genome-wide linkage scan in seven ultiplex psoriatic families from Tunisia. METHODS: Following single nucleotide polymorphism (SNP) genotyping on the Affymetrix 10K SNP array, we performed nonparametric linkage (NPL) multipoint analyses to identify genotypes and obtain evidence for linkage with psoriasis across the genome. RESULTS: No chromosomal region gave consistent evidence for linkage, providing evidence for genetic heterogeneity in Tunisian psoriasis families. Significant evidence for linkage of psoriasis to chromosome 2p12 was seen in one family. We also identified several regions of tentative psoriasis linkage on chromosomes 2q, 4q, 6p, 11q, 12q, 9q and 13q. One family exhibiting suggestive evidence for linkage to 17q25 (PSORS2) was identified and all affected members harboured a p.Gly117Ser mutation in CARD14 (caspase recruitment domain family, member 14), recently reported to lead to psoriasis in a large family from the U.S.A. CONCLUSIONS: Our results support the genetic heterogeneity of psoriasis in the Tunisian population, provide confirmatory evidence for a novel psoriasis locus at chromosome 2p12 and reveal a psoriasis family with a mutation at PSORS2.

Characterization of IncA/C conjugative plasmid harboring bla TEM-52 and bla CTX-M-15 extended-spectrum ß-lactamases in clinical isolates of Escherichia coli in Tunisia.

To characterize the extended-spectrum ß-lactamases (ESBLs) as well as their genetic environment in different isolates of Escherichia coli from patients with repeated urinary tract infections, large multidrug resistance (MDR) plasmids have been found. Definitive evidence for the presence of an A/C incompatibility complex (IncA/C) plasmid in the MDR isolates was provided by the probing of plasmids extracted from the clinical isolates. Conjugation experiments showed that bla genes were transferred by conjugation from the ten E. coli clinical isolates to E. coli XL1-Blue recipient. A comparative restriction fragment length polymorphism (RFLP) analysis of these plasmids showed that they are genetically similar, while the overall similarity of these plasmids supports the likelihood of recent movements among these E. coli isolates. Polymerase chain reaction (PCR) amplification and sequencing of the amplicons showed that the IncA/C plasmids harbor two ESBLs, identified as TEM-52 and CTX-M-15. Analysis of the plasmid DNA surrounding the bla (CTX-M-15) gene in the clinical isolates under study revealed a partially truncated fragment of ISEcp1 tnpA transposase. This result indicates the variety of genetic events that have enabled associations between ISEcp1 sequences and bla (CTX-M-15) genes in these clinical isolates.

Adiponectin expression and metabolic markers in obesity and Type 2 diabetes.

BACKGROUND: Adiponectin has emerged over the last decade as a key adipokine linking obesity, insulin resistance, and Type 2 diabetes. However, the molecular mechanisms controlling adiponectin expression in adipose tissue are not fully elucidated. Furthermore, increasing evidence indicates that peroxisome proliferator-activated receptor- γ (PPAR-γ) plays an important, and beneficial, role in modulating adiponectin expression. AIM: The aim of the present study was to assess the separate role of obesity and Type 2 diabetes in the relationship between endogenous PPAR-γ signaling and adiponectin expression in subcutaneous adipose tissue. SUBJECTS AND METHODS: Enzyme-linked immuno sor bent assay and real time quantitative PCR analysis were carried out in overweight, obese, and/or diabetic Tunisian patients who underwent an abdominal surgery. RESULTS: These results collectively indicate that circulating levels of adiponectin were decreased in all overweight, obese, and/or diabetic (p<0.001). However, the subcutaneous mRNA expression of adiponectin was reduced only in diabetics (p<0.01) but presents some discrepancies in obese individuals. Moreover, mRNA levels of adiponectin were positively correlated with levels of mRNA encoding PPARγ and its heterodimeric partner retinoid X receptor-α (RXR-α), in both obese and diabetic patients. CONCLUSION: Our study on Tunisian patients shows impaired regulation of circulating and mRNA adiponectin levels dependent of metabolic disorders in obesity and Type 2 diabetes. The data suggest that subcutaneous adipose tissue may play an important role in modulating adiponectin expression in diabetes and obesity. Moreover, adiponectin mRNA could be potentially regulated by endogenous PPARγ/RXRα-dependent pathways.

Do smoking and polymorphisms in xenobiotic metabolizing enzymes affect the histological stage and grade of bladder tumors?

Cigarette smoking and genetic susceptibility are the two factors most closely associated with bladder cancer development. This study sought to determine the effect of smoking and genetic polymorphisms in xenobiotic metabolizing enzymes on the histological stage and grade of bladder tumors in Tunisian patients. A total of 97 patients with urothelial cell carcinomas were examined with respect to smoking status, NAT2 (N-acetyltransferase 2), GSTM1 and GSTT1 (glutathione S-transferase Mu 1 and teta 1) genotypes distribution. Our data have reported that tobacco; NAT2, GSTM1 and GSTT1 genotypes were not associated with bladder tumor stage. When we studied the superficial bladder tumor group, we have shown that in smokers tobacco was associated with the development of low-grade tumors. Conversely, non-smoker patients carrying altered NAT2 genotypes were with a 3.67-fold increased risk of developing superficial high-grade tumors (P = 0.02; RR = 3.67; 95% CI: [1.40-9.62]).

Interleukin 10 promoter region polymorphisms in inflammatory bowel disease in Tunisian population.

OBJECTIVE: To test whether IL-10 promoter region polymorphisms are associated with susceptibility to inflammatory bowel disease, we examined the contribution of interleukin- 10 (IL-10) gene polymorphisms to Crohn's disease (CD) and Ulcerative colitis disease (UC) occurrence and also to CD phenotype. MATERIELS AND METHODS: SNPs at positions -627 (C > A) and -1117 (G > A) in the IL-10 promoter were determined in a sample of 105 Tunisian patients with IBD (75 CD and 30 UC) and 90 matched healthy controls. RESULTS: The 627 CA genotype is associated with ileal location (p = 0.015) and with stricturing (p = 510-3) and penetrating (p = 310-3) presentation of CD. An additive effect between IL10 variants and CARD15 3020 insC mutation (p = 0,006) on severe forms of CD was shown. CONCLUSIONS: In Tunisian population, the 3020insC insertion in NOD2/CARD15 gene is a marker of susceptibility to CD, while the A allele at position -627 in the IL-10 promoter increases the risk of CD ileal location and severe disease presentation. A genetic epistasis between IL-10 gene polymorphisms and CARD15/NOD2 gene mutation was suggested.

3020insC insertion in NOD2/CARD15 gene, a prevalent variant associated with anti-Saccharomyces cerevisiae antibodies and ileal location of Crohn's disease in Tunisian population.

OBJECTIVE: Our aim is to investigate the relation between CARD15 3020insC mutation, anti-Saccharomyces cerevisiae antibodies (ASCA) and disease phenotype, in Tunisian inflammatory bowel disease (IBD) patients. MATERIALS: A hundred Tunisian patients with IBD (75 Crohn's disease CD and 25 ulcerative colitis UC) and 60 matched healthy controls were studied. METHODS: CARD15 mutation was analysed by using an allele-specific polymerase chain reaction and sequencing. Assessment of ASCA in serum was performed by ELISA. RESULTS: The frequency of the mutation was significantly higher in Crohn's disease than in control (p = 0,0005; OR = 20.45; CI 95% = 2.86-413.85) and did not differ statistically in UC group (p = 0, 05) from control. ASCAs were present in 60% of CD and 20, 8% of UC. CONCLUSION: This study suggests that in northern Tunisian population, 3020insC mutation in NOD2/CARD15 gene is a prevalent mutation leading to the typical Crohn's disease including ileal location, stricturing and penetrating clinical types and ASCA expression.

No evidence of the APC D1822V missense variant's pathogenicity in Tunisian patients with sporadic colorectal cancer.

OBJECTIVES: Sporadic colorectal cancer is influenced by numerous single nucleotide polymorphisms (SNPs), each with minor effects on the cancer risk. This study seeks to determine whether there is any association of the I1307K, E1317Q and D1822V variants within the Adenomatous polyposis coli gene (APC) and risk to develop colorectal cancer in Tunisian population. METHODS: Direct sequencing was used to investigate three SNPs in the APC in 48 Tunisian sporadic colorectal cancer cases and 63 controls. RESULTS: There was no statistically significant association between the I1307K, E1317Q and D1822V variants investigated and colorectal cancer risk. CONCLUSION: The lack of association may show that these variants selected for this study are not involved in the colorectal carcinogenic process. Otherwise, the eventual biological effect is so little to go undetected, unless increasing the sample size.

Detection of cytokeratin 19 mRNA and CYFRA 21-1 (cytokeratin 19 fragments) in blood of Tunisian women with breast cancer.

Cytokeratin 19 (CK19) is an acidic protein of 40 kDa that is part of the cytoskeleton of epithelial cells. It is highly expressed by all epithelial cells and represents a useful indicator of epithelial differentiation. The soluble fragment of CK19 (CYFRA 21-1) can be a useful circulating tumor marker and can be detected in the serum of cancer patients. The development of metastasis in patients with cancer of epithelial origin is due to the migration of tumor cells from the original tumor to distant organs. In order to detect micrometastasis in patients with breast cancer, we evaluated and compared CK19 gene expression using RT-PCR in blood samples collected from 80 healthy women and 80 patients with localized or metastatic breast cancer. The concentration of the soluble CK19 fragment CYFRA 21-1 was measured in serum of all study subjects by radioimmunoassay employing specific monoclonal antibodies. The relationship between the expression of this molecular marker and clinical stage, tumor differentiation and CK19 mRNA transcripts was investigated. We found that CK19 mRNA expression in blood (as a direct index of the presence of circulating tumor cells) was not correlated with CYFRA 21-1.

Y chromosome microsatellite variation in three populations of Jerba Island (Tunisia).

Six Y-chromosome linked microsatellites were typed in a sample of 135 unrelated males representing three different ethnic groups: Arabs, Berbers and Blacks of Jerba Island (Tunisia). Analysis of variation at the six Y chromosome STRs showed significant differences in allele distributions between the Black group and the two other Islander groups. The Black group revealed the highest level of genetic diversity as compared to Arabs and Berbers, while the latter group was the most homogeneous. Allele frequencies obtained for the three islander groups analysed were compared to data available for some European, Mediterranean and African populations. Principal-coordinate analyses showed genetic differentiation between the three geographically closed groups of Jerba. The absence of the YAP insertion marker and the position of Arabs and Jerban Blacks near the European cluster would suggest their relative 'admixture' with European populations.

A study of Gm allotypes and immunoglobulin heavy gamma IGHG genes in Berbers, Arabs and sub-Saharan Africans from Jerba Island, Tunisia.

The Gm polymorphism of human IgG immunoglobulins was investigated in three different ethnic groups--Arabs, Berbers and 'dark-skinned people'--on Jerba Island, Tunisia. The genetic relationships among these groups and several populations from North Africa, sub-Saharan Africa, west Asia and Europe were analysed by principal coordinate analysis, Fst significance testing, and analysis of molecular variance based on haplotype frequencies. The results revealed a non-significant genetic differentiation between Arabs and Berbers from Jerba. However, the Jerbian population of sub-Saharan African origin was close to Ethiopians. Gene flow among the three Jerbian populations, as well as an East African origin of the dark-skinned individuals, is proposed to account for the observed genetic pattern. However, the genetic diversity observed among the different Tunisian populations did not show any significant correlation with either geographic or linguistic differentiation. A preliminary analysis of the restriction fragment length polymorphism of the IGHG genes in Arabs and Berbers from Jerba confirmed the close genetic relationship between the two populations. However, it also indicated a lower level of genetic diversity in the Berbers, which may be explained by more rapid genetic drift due to longer isolation on the island.

[Tuberculosis of the cavum, report of two cases]. / La tuberculose du cavum, à propos de 2 cas.

The authors report two cases of nasopharynx tuberculosis. This location is rare or misestimated. The sarcoidosis, the Wegener's granulomatis can be discussed. The diagnosis confirmation is based on the histologic features as a caseous necrosis in a langhans reaction cells or as the presence of mycobacterium tuberculosis at a Ziehl-Nielson coloration. The authors insist on the interest of a systematic biopsy of the nasopharynx at the presence of a nasopharynx lesion or a primitive cervical lymph-nodes. A bacteriologic investigation have to be done before the beginning of the specific treatment.

[Anomalies of the 1st branchial arch. Apropos of 3 cases]. / Les anomalies de la 1re fente branchiale. A propos de 3 observations.

The authors report three cases of first branchial cleft anomaly in three patients treated in O.R.L. Service of H. Thameur Hospital of Tunis. After an embryologic and a classification discussion, they expose the etiologic data and insist on the extreme rarity of these malformations (1-8% of the branchial abnormalities). To establish a positive diagnosis, some specific clinic data have to be known, so much the chirurgical management can be began. The operative difficulty is consecutive to the connection with the VII nerve

[Parotid tuberculosis. Apropos of 2 cases]. / La tuberculose parotidienne. A propos de 2 cas.

The authors report 2 cases of parotid gland tuberculosis treated in the O.R.L. Service of C.H.U. H. Thameur, Tunisia. It's very rare infection even in the countries where the tuberculosis is common (Kuruvilla) (1981) (3). The preoperative diagnosis is difficult with a pleomorphic adenoma, a sarcoma or every parotid tumor. A skin's fistula will help the diagnosis which is confirmed by pathology and bacteriology. The treatment consist in a operative management with specific antibiotics. The prognosis is commonly well.