Comparison of Mineral Contents in Three Different Tobacco Formulations / 生物医学与环境科学（英文）

We identified and quantified a variety of mineral elements in 18 tobacco samples purchased from a Tunisian market. In total, 25 mineral elements have been measured in cigarettes, water pipe tobacco, and smokeless tobacco using inductively coupled plasma-optical emission spectroscopy following microwave-assisted digestion. Statistical analyses were performed using SPSSTM, version 18.0. The lowest concentrations of all studied elements were observed in water pipe tobacco. Significantly higher concentrations of Al, Fe, Mg, Na, Ca, Cr, and Co were found in smokeless tobacco, while cigarettes brands contained the highest concentrations of K, Mn, Ni, Ba, and Sr. There was no significant difference between the mineral contents of local and foreign cigarettes and conventional and light cigarettes. Our findings demonstrated that local smokeless tobacco appears to be the most hazardous tobacco type. The concentration of minerals in light cigarettes was not significantly different from the concentration in conventional cigarettes.

[The role of biochemical markers of bone turnover in the diagnosis of osteoporosis and predicting fracture risk]. / Intérêt des marqueurs du remodelage osseux dans le diagnostic de l'ostéoporose et la prediction du risqué de fracture.

BACKGROUND: Currently, for the diagnosis of osteoporosis, we search risk factors and measure bone mineral density (BMD) by DXA method. However, bone turnover markers, unused still in practice, have shown an interest especially in the prediction of fracture risk. aim: To determine the relationship between bone markers, BMD and osteoporotic fracture. methods: Prospective study of 65 women referred for measure of BMD during the period between May and August 2010. Each patient had a dosage of serum bone formation markers: osteocalcin (OC) and N-terminal propeptide of type I collagen (P1NP) and bone resorption markers: serum and urinary C-terminal telopeptide of type I collagen (ß-CTX or CrossLaps) as well as parathyroid hormone and calcium. Risk factors of osteoporosis were identified in each case. results: Our 65 women had a mean age of 58.6 ± 12.1 years. The majority (83%) were menopausal women. Osteoporosis was found in 52%, osteopenia 26% and normal BMD 22% of cases. An increase in bone turnover markers was correlated with menopause (p = 0. 001 for the OC, p = 0.016 for urinary CTX), a low body mass index (p = 0.015 for OC, p = 0.042 for serum CTX) and osteoporosis (p <0.001 for P1NP, p <0.001 for serum and urinary CTX). Corticosteroid therapy was correlated with a decrease in bone formation markers (p = 0.002 for P1NP). The presence of fracture was only associated with increased urinary CTX (p = 0.05). CONCLUSION: Bone turnover markers increase in menopausal women and in case of low BMD. However, their contribution in the diagnosis of osteoporosis is low. They are rather an interest in the prediction of fracture risk.

Changes in Urinary Stone Composition in the Tunisian Population: A Retrospective Study of 1,301 Cases

BACKGROUND: Studies that evaluate the effect of age on stone composition are scarce. The aim of this study was to highlight the changes in epidemiological characteristics (stone composition and location) of urolithiasis according to patients' age. METHODS: We studied 1,301 urolithiasis patients with age ranging from 6 months to 92 yr (781 males and 520 females). Stone analysis was performed using a stereomicroscope and infrared spectroscopy to determine the morphological type and molecular composition of each stone. RESULTS: The annual average incidence of new stone formation was 31.7 per 100,000 persons. In 71.8% of cases, calculi were located in the upper urinary tract. Compared to other age groups, children and old men were more affected by bladder stones. Calcium oxalate monohydrate was the most frequent stone component, even though its frequency decreased with age (59.5% in young adults and 43.7% in the elderly, P<0.05) in favor of an increase in uric acid stones (11.5% in young adults and 36.4% in the elderly, P<0.05). Struvite stones were rare (3.8%) and more frequent in children than in adults. CONCLUSIONS: The analysis of these data showed that urinary stones in Tunisian patients are tending to evolve in the same direction as the stones in patients from industrialized countries.

Influence of hypercalcic and/or hyperoxalic diet on calcium oxalate renal stone formation in rats.

OBJECTIVE: To test whether increasing dietary calcium intake prevents calcium oxalate stone formation when the diet is oxalate-rich. Material and methods. Four groups, eight rats in each, were subjected to a lithogenic diet by the addition of 0.5% ethylene glycol to drinking water for 3 weeks. The first group, used as a control, simultaneously received a standard diet. The second group was supplemented with calcium at 500 mg/100 g of diet and the third group with oxalate at 3 g/100 g of diet. The diet given to the last group was supplemented with similar doses of calcium and oxalate. One day before the end of treatment, each animal was placed in a metabolic cage to collect 24-h urine samples and determine urinary parameters. The kidneys were removed to determine calcium oxalate deposits and for histological examination. RESULTS: The number of calcium oxalate crystals in renal tissue was highest in the oxalate group and calcium oxalate deposits were also found to be elevated in this group. Hyperoxaluria and hypocitraturia, induced by a oxalate-rich diet, seemed to be the major causes contributing to aggravated renal stone formation. The protective effect of dietary calcium supplementation, which was clear in the calcium + oxalate group, was probably due to intestinal binding of oxalate by calcium, thereby reducing urinary oxalate excretion. CONCLUSION: Increased dietary calcium intake can prevent calcium oxalate stone formation only when the diet is oxalate-rich.