Evaluation of the reliability of human teeth matrix used as a biomarker for fluoride environmental pollution.

Environmental contamination by heavy metals has been a matter of great concern in many countries for several decades. Human exposure to such elements may cause adverse health effects and young children are particularly at risk. Many matrixes have been used for determination of metal exposure levels. Hard tissues such as teeth and bones have some advantages compared to other matrix. Dental tissues are considered to be suitable for long-term metal exposure due to their stability, resistance to physical and chemical degradation and their good preservation over time. Several studies have analyzed the teeth of animals for assessment the relationship between increased fluoride exposure and dental fluorosis, however few studies have been conducted on human teeth. Thus, the aim of the present study was to assess the reliability of human teeth matrix used as a biomarker for fluoride environmental pollution in Tunisia, and to evaluate the relationship with place of residence, age, dental caries and sex. Teeth samples (n=123) were collected from individuals living in Gafsa (fluoride-polluted area which inhabitants are to a great extent exposed to heavy metals) and Tunis (non polluted area). Samples were analyzed using a potentiometric method. The fluoride concentration was found to be significantly higher in teeth from Gafsa samples than those from Tunis. Their control levels were respectively 6793.1µg/g and 1068.8µg/g. The results indicate that there is a clear relation between fluoride concentration and residence of living. An increased level of dental fluorosis in fluoridated communities has been used to evaluate historical chronic exposure to fluoride in these communities, despite constant fluoride levels in the drinking-water. The fluoride concentration was also observed to be significantly increased in polluted area with age and in carious teeth whereas, no significant difference was observed for sex. Our study confirms well that human teeth used as a bioindicator for environmental pollution provide good chronological information on exposure, and highlighted the risks incurred by consumers living in such polluted area.

Optimization of morphine extraction method for the assay of its urinary 3-glucuronideconjuguate by gas chromatography-mass spectrometry.

In the field of doping, a great interest is carried for the analysis of morphine, a powerful narcotic analgesic opiate which use is prohibited during competitions. In order to confirm the abnormal analytical result in our anti-doping laboratory, a sensitive and selective gas chromatography-mass spectrometry (GC-MS) method was performed for the quantification of urinary morphine. As sample preparation is a key step for the determination of drugs in biological samples, the aim of this work consists of the optimization of the urinary human sample pretreatment conditions before quantification by GC/MS. Enzymatic hydrolysis associated with liquid-liquid extraction constitute the major pre-treatment steps. Our study has first focused on the optimization of the extraction solvents then to enzymatic hydrolysis which morphine is released from its glucuronide conjugated form. Onboard premiums, a study involving the effect of "amount of enzyme", "incubation temperature" and "duration of hydrolysis" was conducted. This univariate study has enabled us to evaluate the influence of each of these operating variables on the area ratio of morphine to the internal standard (Amorphine/AIS) response and to set the experimental fields for each one of them. Based on these results, an experimental design was established using the Box-Behnken model to determine, by multivariate analysis, the optimal operating conditions maximizing the "Amophine/AIS" response. After validation, the analysis of response surface makes it possible to set the optimum operating conditions, which the ratio "Amorphine/AIS" is maximized. The retained conditions for enzymatic hydrolysis are 160µl of Escherichia coli glucuronidase enzyme during 6hours of incubation at a temperature of 36°C. The solvent mixture Methyl-t-Butyl Ether/isopropanol (4:1, v/v) was selected since it has improved morphine extraction from the urinary matrix allowing a gain of 50% when compared to that used in our routine laboratory. Our developed extraction method can be successfully applied for our forensic anti-doping analysis of morphin in human sample urine.

[Ectopic thymus: A rare cause of neck mass in children]. / Thymus ectopique : une cause rare de tuméfaction cervicale chez le nourrisson.

INTRODUCTION: Ectopic cervical thymus (ECT) is a rare embryological abnormality in children. It can be revealed by a compressive neck mass mistaken for a malignant tumor. Through a new case of ECT, we review the embryopathogenesis, diagnostic difficulties and therapeutic features. CLINICAL OBSERVATION: A 19-month-old girl presented a right cervical mass that quickly increased in size, causing intermittent dyspnea. The physical examination objectified a 6-cm, soft and compressible, painless right cervical tumefaction, extending from the mastoid area to the ipsilateral supraclavicular fossa. The diagnosis suggested based on CT was a cervicomediastinal cystic lymphangioma. The diagnoses discussed based on MRI were a collection of necrotic lymphadenopathy, rhabdomyosarcoma or neurofibroma debris. The mass was surgically excised through a laterocervical incision. A whitish multilobular tissular mass was found, adherent to the neurovascular axis of the neck. Pathological examination concluded in normal ectopic thymus tissue. The postoperative course was uneventful. CONCLUSION: Although ECT is a rare benign anomaly, it should be considered as a possible cause of a neck mass in children. Surgery is the curative treatment. Before surgery, the presence of a mediastinal thymus must be confirmed to avoid the risk of a total thymectomy in children. MRI is helpful in delineating thymic ectopia compared to the mediastinal thymus.

[Simultaneous intra- and extra-uterine pregnancies. Apropos of 6 cases]. / Grossesses intra- et extra-utérines associées. A propos de 6 cas.

Six cases of simultaneous intra- and extra-uterine pregnancies are described by the authors. The rate of 1/5000 deliveries is considerably higher than described in the literature. The association of the two conditions is seldom thought of and has never been diagnosed before the extra-uterine pregnancy has ruptured. The initial picture seems to be that of an intra-uterine pregnancy with a threatened abortion in 83% of the cases. Only 33% of the intra-uterine pregnancies reached term. The prognosis could be improved if the doctor were to think of the possibility more often.

[Stress urinary incontinence in women. Epidemiologic inquiry. Apropos of 500 cases]. / L'incontinence urinaire d'effort chez la femme. Enquête épidémiologique. A propos de 500 cas.

Nearly 50% of women in Tunisia have urinary incontinence, and 30% of these are highly embarassed. This condition is under-estimated in Tunisia by doctors in as far as its functional effects are concerned because the country has other diseases which are more urgent and take priority. Stress incontinence causing invalidism is very frequent: 31.4%. The principal factors that lead to it are home delivery, multiparity, menopause and large babies. There are two frequent associated conditions: incontinence during pregnancy and cystocoele. A contribution is made by the clinical diagnosis, but if investigations stop there a definite diagnosis cannot be made and therefore there is a risk of failure of treatment. In fact the treatment should be according to the cause: it is medical when are purely urinary troubles and surgical or physiotherapeutic when there is true stress incontinence. The best treatment would be to prevent the condition by good obstetrics and this by better methods of delivering the babies.