Modelling of Reactive Black 5 decolourization in the presence of heavy metals by the newly isolated Pseudomonas aeruginosa strain Gb30.

AIM: The effect of heavy metals presence on the decolourization of Reactive Black 5 by Pseudomonas aeruginosa was evaluated. METHODS AND RESULTS: In the current study, a newly isolated strain identified as P. aeruginosa strain Gb 30 was selected for its ability to remove high concentration of Reactive Black 5 and resistance to several heavy metals (Cu2+ >Zn2+ >Cd2+ >Cr6+ ). Strain Gb30 was used to assess the effect of heavy metals presence on RB5 decolourization. The strain growth exhibited different responses at a fixed concentration of EC50 (10 h) for each heavy metal. The addition of Zn2+ and Cd2+ had no effect on decolourization yield after 24 h of incubation, whereas Cr6+ and Cu2+ ions reduced decolourization up to 17%. In order to understand the relationship between heavy metals contamination and decolourization, experimental data relating the initial decolourization rate of RB5 to the concentrations of single and associated heavy metals were fitted to three different inhibition kinetic models. CONCLUSIONS: In this study, we showed that P. aeruginosa strain Gb30 could be used for dye removal even at high concentrations of heavy metals. The developed models could provide basic information that may help for the best management of the bacteria-mediated decolourization process at the industrial scale. SIGNIFICANCE AND IMPACT OF THE STUDY: This study opens new directions for the management of textile industry wastewaters containing dyes and heavy metals using bioaugmentation by P. aeruginosa strain Gb30.

[Cerebral venous thrombosis: Prospective etiological study of 26 Tunisian patients]. / La thrombose veineuse cérébrale : étude étiologique prospective de 26 patients tunisiens.

PURPOSE: The aim of the present study is to provide a clinical and etiological analysis of cerebral venous thrombosis (CVT) in the Tunisian population. METHODS: This is a prospective monocentric study including 26 patients referred to the Neurology Department of the Military Hospital of Tunis between January 2005 and January 2008. The diagnosis of CVT was confirmed in all patients by magnetic resonance imaging (MRI) and angiography. The clinical and biological risk factors of cerebral venous thrombosis were analyzed. The average follow-up was 18 months (range six to 30). The outcome was assessed clinically with the modified Rankin scale and with MRI. RESULTS: Mean age was 38.26 years, predominantly females (sex-ratio 4.2). The clinical onset was acute in 88.46% of the cases. Headache was the most common inaugural sign (84.6%). Lateral and superior longitudinal sinuses were the most commonly involved with equal frequency (61.53%). Parenchymal lesions were frequently noted (77%), especially hemorrhagic infarcts (46.15%). The causes of CVT were variable and usually combined (85%). Specifically, thrombophilia and obstetric-gynecological causes were predominant with a prevalence of 61.5 and 42.3%, respectively. Septic causes (38.46%) are also frequent, mainly oral infections (27%). Outcome was favorable in 77% of patients given heparin therapy, followed by oral anticoagulants and antibiotics as needed. CONCLUSION: Our Tunisian population presented distinct clinical features compared with previous studies, including a high frequency of thrombophilia and gyneco-obstetrical disorders as well as infectious causes.

[Polymorphisms of the UDP-glucuronosyltransferase 1-A1 gene in Tunisian population]. / Polymorphismes alleliques du gene UDP-glucuronosyltransferase 1A1 dans une population Tunisienne.

The UDP-glucuronosyltransferase 1A1 gene that encode the enzyme UGT1A1 responsible for glucuronidation undergoes several variations that may affect the enzymatic activity or expression and which are the cause of metabolic disorders related to the glucuronidation of bilirubin, such as Gilbert's syndrome and Crigler Najjar's syndrome. Among the most common variations, there is the repeat polymorphism A (TA) n TAA in TATA box and biallelic mutation G211A in exon 1. We consider in this work to determine their frequencies in a healthy population. The polymorphism A (TA) n TAA showed that genotype [TA7/TA7] was described as being associated with Gilbert's syndrome and was encountered in 11% of the population studied. This percentage is close to the value described in the Caucasian population, estimated at 10%. Concerning the polymorphism G211A, our results show that the mutated allele is encountered in 15.7% of our study population. This frequency differs greatly from that reported for Caucasians and Afro-Americans but it is similar to that perceived at the Japanese. All these results suggest that the Tunisian population appears to be heterogeneous view UGT1A1 gene mutation status. Regarding the origins and distribution of such polymorphisms in our population, the study reveals a high haplotypic haplotype (TA) 6-G considered ancestral. The comparison of the haplotype structure generally leads to the development of a hypothetical tree of the origin and spread of different haplotypes.

[Cerebral aspergillosis in immunocompetent patients: three case reports]. / Aspergillose cérébrale chez le sujet immunocompétent. A propos de trois cas.

INTRODUCTION: Cerebral aspergillosis is a severe disease most commonly suspected in immunocompromised patients. CASE REPORT: We report herein three cases of cerebral aspergillosis in immunocompetent adults. Sinus involvement was noted in two cases, but there was no extracerebral involvement in the third case. Mycology samples provided the diagnosis in two cases. In the third case, cerebral imaging visualized a tumor; the patient underwent surgery and the pathology exam of the surgical specimen established the diagnosis. All patients were given antifungal treatment and achieved a good outcome. CONCLUSION: Cerebral aspergillosis is highly uncommon in immunocompetent patients. In addition to immunodepression, the notion of pulmonary or ENT involvement may be suggestive. In the brain, aspergillosis mainly involves the basal nuclei and the thalamus.