Mohamed Kacem Ben Fradj

Association of maternal homocysteine and vitamins status with the risk of neural tube defects in Tunisia: A case–control study

BACKGROUND This study was conducted to determine whether low folate and vitamin B12 levels, as well as high homocysteine levels in pregnant women are associated with neural tube defects (NTDs) in Tunisia. METHODS A total of 75 NTDs pregnancies and 75 matched controls were included in the study. Their vitamin B12, folate, and red blood cell folate concentrations were measured using a radio-immunoassay kit and total homocysteine concentrations were determined using a fluorescent polarization immunoassay. RESULTS Vitamin B12 and folate concentrations were lower in NTD-affected pregnant women than in controls (respectively, p = 0.009 and p < 0.001). Total homocysteine concentration was significantly higher in the NTDs group than in controls (p = 0.008). In the case group, the folate levels were positively related with vitamin B12 levels (r = 0.54; p < 0.001) and negatively correlated with total homocysteine levels (r = -0.19; p = 0.04). Besides, red blood cell folate levels were positively correlated with folate levels (r = 0.24; p = 0.02) and negatively correlated with total homocysteine levels (r = -0.37; p = 0.001). CONCLUSION Lower concentrations of folate and vitamin B12 are related to the increased risk of NTDs. Both folate and vitamin B12 intake insufficiency could contribute to the increased risk of NTDs. A dietary supplement, combining folate and vitamin B12, might be an effective measure to decrease the NTDs incidence in Tunisia.

Bladder Cancer is Associated with Low Plasma 25-hydroxyvitamin D Concentrations in Tunisian Population

abstract Little evidence suggests an impact of vitamin D on bladder cancer risk in Caucasians. This study aimed to investigate association of plasma 25-hydroxyvitamin D (25-OHD) with urothelial bladder cancer (UBC) risk in Tunisians. A case-control study included 250 patients with UBC and 250 healthy controls. Plasma 25-OHD was assessed by a competitive chemiluminescence immunoassay. Vitamin D deficiency and insufficiency were defined as 25-OHD <30 nmol/L and 30 to 49.99 nmol/L, respectively. Logistic regression models adjusting for gender, age, smoking status, duration of smoking, occupational exposure, and season were applied. Vitamin D deficiency (50.4% vs. 34.8%; P < 0.001) and insufficiency (40.4% vs. 26.8%; P < 0.001) were more frequent in patients than controls. Multivariate analysis showed that UBC is associated with vitamin D deficiency [odd-ratio (95% confidence interval), 3.71 (1.76–7.80); P = 0.001] and vitamin D insufficiency [2.65 (1.40–5.01); P = 0.003]. Other predictors of UBC were female gender, tobacco use, smoking duration, and occupational exposure. Plasma 25-OHD concentrations are low in Tunisian patients with UBC. These findings support experimental and epidemiological evidence of protective role of vitamin D against UBC but could not ascertain causal relationship. Further prospective studies and clinical trials are warranted to check causality.

Vitamin D inadequacy is widespread in Tunisian active boys and is related to diet but not to adiposity or insulin resistance.

Background Vitamin D inadequacy is widespread in children and adolescents worldwide. The present study was undertaken to assess the vitamin D status in active children living in a sunny climate and to identify the main determinants of the serum concentration of 25-hydroxyvitamin D (25-OHD). Methods This cross-sectional study included 225 children aged 7–15 years practicing sports in a football academy. Anthropometric measures were performed to calculate body mass index (BMI), fat mass, and maturity status. A nutritional enquiry was performed including 3-day food records and food frequency questionnaire. Plasma 25-OHD and insulin were assessed by immunoenzymatic methods ensuring categorization of vitamin D status and calculation of insulin sensitivity/resistance indexes. A logistic regression model was applied to identify predictors for vitamin D inadequacy. Results Vitamin D deficiency (25-OHD<12 µg/L) was observed in 40.9% of children and insufficiency (12<25-OHD<20 µg/L) was observed in 44% of children. In a multivariate analysis, vitamin D deficiency and insufficiency were associated with a lower dietary intake of vitamin D, proteins, milk, red meat, fish, and eggs. However, no significant relationship was observed with maturation status, adiposity, or insulin resistance. Conclusions Tunisian children and adolescents are exposed to a high risk of vitamin D inadequacy despite living in a sunny climate. Circulating 25-OHD concentrations are related to the intake of vitamin D food sources but not to maturation status or body composition. Ensuring sufficient and safe sun exposure and adequate vitamin D intake may prevent vitamin D inadequacy in children from sunny environments.

Effect of High-Intensity Interval Training on Plasma Omentin-1 Concentration in Overweight/Obese and Normal-Weight Youth

Objectives: Omentin-1 is a recently discovered adipokine, mainly produced by visceral adipose tissue, which is thought to improve insulin sensitivity. The study aimed to assess the association of plasma omentin-1 with cardiometabolic traits and physical performance and to test its response to high-intensity interval training (HIIT) in obese and normal-weight subjects. Methods: Nine overweight/obese (OG) and 9 normal-weight (NWG) young men performed an 8-week HIIT program. Body composition, physical performance, homeostasis model assessment index for insulin resistance (HOMA-IR) as well as plasma omentin-1and lipid levels were assessed before and after the HIIT program. Results: Baseline plasma omentin-1 was lower in OG than NWG men (359 ± 138 vs. 470 ± 114 ng/ml; p = 0.052). Plasma omentin-1 was related to body fat (r = -0.57; p = 0.03) and LDL-cholesterol (r = -0.49; p = 0.04). There was a trend towards significant association of omentin-1 with BMI (r = -0.47; p = 0.06) and VO2max (r = 0.41; p = 0.09). However, no association was observed with HOMA-IR. Following the HIIT program, omentin-1 concentrations have significantly (p < 0.01) increased in OG (359 ± 138 to 455 ± 126 ng/ml) and NWG men (470 ± 114 to 572 ± 115 ng/ml). In parallel, the cardiometabolic profile has improved with a significant decrease of HOMA-IR in OG. Conclusions: HIIT resulted in a plasma omentin-1 increase and an improvement with regard to cardiometabolic traits in the OG men, which may contribute to modulate insulin sensitivity.

An increase in spina bifida cases in Tunisia, 2008–2011

BACKGROUND The term spina bifida refers to a group of neural tube defects that result in malformations of the spinal cord and the surrounding vertebrae. Though the etiologies of spina bifida remain largely unknown, several risk factors have been identified, including feto-maternal characteristics. AIM OF THE STUDY To discover possible underlying reasons for the increase of spina bifida and identify intervention targets, an investigation was undertaken comparing spina bifida-affected pregnancy notifications in 2008-2011 with notifications in the period 1991-1994. METHODS Characteristics and outcomes of births with spina bifida and pregnancy characteristics of mothers were recorded in the medical chart. Comparisons of pregnancies affected by a spina bifida in 2008-2011 were made with pregnancies affected by a spina bifida in the period 1991-1994. Statistical analysis was undertaken using Poisson regression and Chi-squared tests. RESULTS From 1991 through 1994, the prevalence of identified spina bifida cases was equal to 0.3/10,000 births compared to 1.6/10,000 births in 2008-2011. This increase was statistically significant (P<0.001). The prevalence of females was equal to 0.45 per 10,000 births over the period 1991-1994 compared to 1.88 per 10,000 births during the period 2008-2011. As for males, the prevalence was equal to 0.16 per 10,000 births in 1991-1994 compared to 1.88 in 2008-2011. The difference was statistically significant (P<0.001) between both genders. A mothers age of over 30 years had significant impact on the emergence of spina bifida (P=0.02, OR=3.93, CI=1.23-12.47). As well as, maternal blood type was a significant risk factor for the appearance of spina bifida (P=0.008). Results also had shown that fetal weight and term, gestity and parity were significant risk factors for the occurrence of spina bifida (P<0.05).In this study, results have been interpreted with caution due to analyses not being adjusted. CONCLUSION This analysis highlighted areas where prevention efforts should be strengthened and surveillance data improved.

Decreased Oleic Acid and Marine n − 3 Polyunsaturated Fatty Acids in Tunisian Patients with Urothelial Bladder Cancer

Abstract Fatty acids (FAs) are thought to impact carcinogenesis by affecting cell signaling. A case-control study including 250 patients with urothelial bladder cancer (UBC) and 250 controls was conducted. Plasma FAs composition was assessed using capillary gas chromatography. Associations of individual and classes of FAs with UBC were controlled for the main risk factors for UBC. Plasma FAs profile was different in patients compared to controls. Higher levels (third tertile vs. first tertile) in palmitic acid (PA) [multi-adjusted OR (95% CI), 1.83 (1.14–2.92)], and n − 6:n − 3 FA ratio [4.13 (2.38–7.16)] were associated with increased risk for UBC [multi-adjusted OR (95% CI), 1.83 (1.14–2.92)]. In contrast, higher levels (third tertile vs. first tertile) in oleic [0.54 (0.34–0.86)], dihomo-γ-linolenic (DGLA) [0.47 (0.29–0.74)], eicosapentaenoic (EPA) [0.32 (0.19–0.52)], and docosahexaenoic (DHA) acids [0.33 (0.20–0.53)] were associated with lower risk for UBC. Although the study design does not allow proving causality, the findings suggest a possible protective role of oleic acid and marine n − 3 polyunsaturated FAs (PUFAs) against bladder carcinogenesis.

Haplotype-based association of Vascular Endothelial Growth Factor gene polymorphisms with urothelial bladder cancer risk in Tunisian population

Accumulated data suggested that Vascular Endothelial Growth Factor is a major mediator in vasculogenesis, angiogenesis and recently in tumorigenesis. Therefore, we aimed to investigate for the first time the association between VEGF gene variants (‐2549I/D (rs35569394), ‐2578C/A (rs699947), and +936C/T (rs3025039)) with urothelial bladder cancer (UBC) in Tunisian population.

Effects of high-intensity interval training on body composition, aerobic and anaerobic performance and plasma lipids in overweight/obese and normal-weight young men

To examine the effects of short high-intensity interval training (HIIT) on body composition, physical performance and plasma lipids in overweight/obese compared to normal-weight young men. Nine overweight/obese and nine normal-weight men (control group) aged 17 to 20 years underwent a HIIT programme three times per week for eight weeks. Body composition, indices of aerobic [maximal aerobic velocity (MAV) and maximal oxygen uptake (VO2max)] and anaerobic [squat jump (SJ), counter-movement jump (CMJ), five-jump test (FJT), 10-m and 30-m sprint] performances, as well as fasting plasma lipids, were assessed in the two groups at PRE and POST HIIT. The HIIT programme resulted in significant reductions in body mass (-1.62%, P=0.016, ES=0.11) and fat mass (-1.59%, P=0.021, ES=0.23) in obese, but not in normal-weight subjects. MAV (+5.55%, P=0.005, ES=0.60 and +2.96%, P=0.009, ES=0.82), VO2max (+5.27%, P=0.006, ES=0.63 and +2.88%, P=0.009, ES=0.41), FJT (+3.63%, P=0.005, ES=0.28 and +2.94%, P=0.009, ES=0.52), SJ (+4.92%, P=0.009, ES=0.25 and +6.94%, P=0.009, ES=0.70) and CMJ (+6.84%, P=0.014, ES=0.30 and +6.69%, P=0.002, ES=0.64) significantly increased in overweight/obese and normal-weight groups, respectively. 30-m sprint time significantly decreased in both groups (-1.77%, P=0.038, ES=0.12 and -0.72%, P=0.030, ES=0.16). Plasma total cholesterol (-11.8%, P=0.026, ES=0.96), LDL cholesterol (-11.9%, P=0.050, ES=0.77) and triglycerides (-21.3%, P=0.023, ES=1.08) significantly decreased in the obese group, but not in the normal-weight group. The eight-week HIIT programme resulted in a slight improvement in physical fitness and a significant decrease in plasma lipids in the obese. Short duration HIIT may contribute to an improved cardiometabolic profile in the obese.