Chemical composition, antibacterial and cytotoxic activities of the essential oil from the flowers of Tunisian Convolvulus althaeoides L.

This study describes the chemical composition and evaluates the antibacterial and the cytotoxic effects of the essential oil from the flowers of Convolvulus althaeoides. Its chemical composition, determined by GC and GC-MS, is reported for the first time. A total of 24 compounds, accounting for 95.5% of the total oil, have been identified. The oil was characterised by a high proportion of sesquiterpene hydrocarbons (36.3%), followed by oxygenated sesquiterpenes (34.7%) and oxygenated monoterpenes (24.5%). The main compounds were germacrene D (12.5%), T-cadinol (11.8%) and verbenone (6.9%). The essential oil was tested for its antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis and the clinical strain Acinetobacter sp. as well as facts cytotoxic activity towards the human breast cancer cells MCF-7. This oil did not exhibit significant antibacterial activity against the tested bacteria; however, it exerted a significant cytotoxic activity against the tested cell line (IC50 = 8.16 µg/mL).

[Study of cardiovascular risk factors in Tunisian patients with recent type 2 diabetes]. / Étude des facteurs de risque cardiovasculaire chez le diabétique de type 2 Tunisien récemment découvert.

OBJECTIVE: To study the frequency of silent myocardial ischemia (SMI) in Tunisian patients with recent type 2 diabetes and identify cardiovascular risk factors directly in relation with SMI. PATIENTS AND METHODS: One hundred and twenty diabetics and sixty healthy people have benefited from blood sampling, electrocardiogram and exercise test. RESULTS: The frequency of SMI was 21% in diabetics and 3% in healthy people (P=0.01). Obesity and hypertension were higher in diabetics than in healthy people (P=0.001 and P<10(-4)). Using unvaried analysis for risk factors with the presence of SMI in diabetics, we found that age greater than 60 yrs, male sex, sedentary and smoking were significantly correlated with SMI; respectively P=0.004, 0.01, 0.009 and 0.03. The SMI was found in 37% of diabetics with high blood pressure vs 8% in diabetics with normal blood pressure and was correlated with hypertriglyceridemia, hypoHDLemia and microalbuminuria. Patients with SMI had at least two cardiovascular risk factors apart from diabetes among those: age greater or equal to 60 yrs, male sex, smoking, hypertension, dyslipidemia and family history of early coronaropathy. Chronic inflammation and hyperhomocysteinemia were significantly correlated to SMI; OR=4.2 and 3.8. In addition, SMI was found in one diabetic over three who had bad glycemic control. Using multivariate analysis, only age greater or equal to 60 yrs, smoking, hypertension, hyperhomocysteinemia and hypertriglyceridemia were risk factors directly in relation with SMI in type 2 diabetes. CONCLUSION: The assessment of global cardiovascular risk from the moment of discovering type 2 diabetes and the early screening of SMI should be necessary.

["Smoker's paradox" and reperfusion's strategy in acute myocardial infarction]. / "Paradoxe des fumeurs" et stratégie de reperfusion à la phase aiguë de l'infarctus du myocarde.

UNLABELLED: Previous studies have shown that smokers with acute myocardial infarction (AMI) treated by thrombolysis have lower mortality rates than nonsmokers, a phenomenon often termed "smoker's paradox". This "smoker's paradox" has been rarely studied in case of primary angioplasty. AIM OF THE STUDY: To evaluate the impact of smoking status on the early mortality of patients admitted with AMI with regard to the strategy of reperfusion (intravenous thrombolysis versus primary angioplasty). PATIENTS AND METHODS: Study undertaken from the Monsatir registry of ST elevation MI including 688 patients having had either a hospital or a prehospital thrombolysis (n=397) or a primary angioplasty (n=291). Among those patients, 482 (70.1%) were active smokers. RESULTS: In the thrombolysis group, the prevalence of hypertension, diabetes and anterior location of MI was significantly less among smokers. In the group primary angioplasty, only diabetes and hypertension were less frequent. The immediate mortality was significantly less among smokers in case of thrombolysis comparatively to non-smokers (5.3 vs 13%; p=0.008). By multivariate analysis, cardiogenic shock (p<0.0001), anterior MI (p=0.03) and active smoking (p=0.03) were independent predictive factors of mortality in case of thrombolysis. A trend toward a lower mortality among smokers was observed in the primary angioplasty group (10 vs 17.6%; p=0.07). CONCLUSION: "The smoker's paradox" seems to be observed mainly among patients having had thrombolysis.

+294T/C polymorphism in the PPAR-delta gene is associated with risk of coronary artery disease in normolipidemic Tunisians.

Peroxisome proliferator-activated receptor delta (PPAR-delta) is a transcription factor implicated in metabolism and inflammation. The +294T/C polymorphism in the PPAR-delta gene is associated with risk of coronary artery disease (CAD) in dyslipidemic women and hypercholesterolemic men. Whether this polymorphism influences the risk of CAD in the absence of dyslipidemia was not known, so we investigated a possible association of this polymorphism with plasma lipid and lipoprotein levels and with risk and outcome of CAD in a normolipidemic Tunisian population. Genotyping was performed by PCR-RFLP in 112 CAD patients and 113 healthy volunteers. The C-allele was significantly more frequent in patients than in controls (0.320 vs 0.189, P = 0.001). This association remained significant after adjustment for age, gender, body mass index, smoking, hypertension, and high-density lipoprotein cholesterol. Subjects carrying either one or two copies of the C-allele had a 2.7-fold higher risk of CAD than subjects homozygous for the T-allele. PPAR-delta genotypes were not associated with lipoprotein concentrations or outcome of CAD. We conclude that PPAR-delta +294T/C polymorphism is an independent risk factor of CAD in normolipidemic Tunisian subjects. The lack of association with lipoprotein concentrations suggests that the effect of the polymorphism on CAD is not mediated through lipoprotein levels in this population and that it may influence the atherosclerotic process through mechanisms involving inflammation.

Detection and molecular characterization of enteric viruses in environmental samples in Monastir, Tunisia between January 2003 and April 2007.

AIMS: A prospective study was performed to characterize the main human enteric viruses able to persist in sewage samples and in shellfish tissues, and to establish the correlation between environmental strains and viral infantile diarrhoea observed in the same area during the same period. METHODS AND RESULTS: A total of 250 sewage (raw and treated) and 60 shellfish samples were collected between January 2003 and April 2007 in Monastir region, Tunisia. Group A rotavirus (RVA) was detected in 80 (32%) sewage samples, norovirus (NoV) in 11 (4·4%) and enteric adenovirus (AdV) in 1 (0·4%). Among 60 shellfish samples collected near sewage effluents, one was contaminated by NoV (1·6%). CONCLUSION: Our data represent the first documentation in Tunisia, combining gastroenteritis viruses circulating in the environment and in clinical isolates. We observed a correlation between environmental strains and those found in children suffering from gastroenteritis during the same period study. This suggests the existence of a relationship between water contamination and paediatric diarrhoea. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results address the potential health risks associated with transmission of human enteric viruses through water-related environmental routes. The research findings will aid in elucidating the molecular epidemiology and circulation of enteric viruses in Tunisia and in Africa, where data are rare.

Relationship between glutathione S-transferase P1 polymorphisms and chronic obstructive pulmonary disease in a Tunisian population.

Chronic obstructive pulmonary disease (COPD) is a multifactorial disease with possible genetic predisposition and involvement of various environmental factors. Several candidate genes have been reported as potentially associated with this lung disease. The glutathione S-transferase P1 gene (GSTP1) was proposed to be involved in susceptibility to develop COPD. It belongs to the GST family, which is a group of phase II enzymes that catalyze the glutathione conjugation of many endogenous and exogenous electrophilic compounds, such as carcinogens, therapeutic drugs, environmental toxins, and oxidative stress products. We conducted a case-control study to investigate genetic polymorphisms of this enzyme [exon 5 (Ile105Val) and exon 6 (Ala114Val)] in 234 unrelated COPD cases and 182 healthy controls from a Tunisian population. Genotyping was carried out using polymerase chain reaction and restriction fragment length polymorphism methods. GSTP1 Ala114/Val114 and Val114/Val114 genotypes were not found in either patients or healthy controls. However, there were differences in the distribution of various exon 5 GSTP1 genotypes between COPD patients and healthy controls. GSTP1 Val105/Val105 was significantly more common in patients compared to controls (OR = 2.67; 95%CI = 1.45-4.92; P = 0.0013). Multivariate logistic regression analysis confirmed a significant relationship between the mutant genotype and COPD (OR = 2.58; 95%CI = 1.31-5.09; P = 0.026), after adjustment for classic risk factors. Analysis of variance showed no correlation between age, body-mass index, pack-years, percentage of predicted FEV1 values, and any of the GSTP1 genotypes. We conclude that subjects with GSTP1 Val105 allele are at higher risk of COPD.

[Malignant otitis externa (2 cases)]. / L'otite externe maligne (à propos de deux observations).

Malignant external otitis is a progressive necrotizing otitis. It's a rare severe and evolutive clinical entities, old diabetics are the most victim. Pseudomonas aeruginosa is the bacteria responsible in the most cases. Prognostic vital can be affected, treatment must be energic, rapid and well adapted. The authors report two old diabetic women presenting a malignant external otitis and discuss etiopathogenic, physiopathologic, diagnosis and treatment of this illness.