Dietary intake and status of selenium in breast milk and serum of lactating mothers in Awka, South East Nigeria.

Background: Selenium is an essential micronutrient for human growth and development. Breast milk is usually the primary source of this nutrient for infants which is fundamental for their healthy brain development; its deficiency can lead to severe neurocognitive outcomes. The concentration of selenium in breast milk is dependent on the maternal diet. Aim: This study assessed associations between maternal diet and levels of selenium concentrations in breastmilk and serum of 124 lactating mothers. Methods: Breast milk and serum samples were collected from lactating mothers whose breast-fed infant was at least one month old. A validated food frequency questionnaire was used to collect information on dietary intake. Descriptive statistics were used to summarize the data while paired t-test was used to determine any statistically significant differences between sample means. Spearman's rank correlation analysis was used to determine associations between breast milk and serum selenium concentrations and study variables. Results: Average time postpartum was 2.9 months while mean concentrations of selenium in breast milk and serum were 6.57 ± 2.69 and 68.48 ± 26.86 µg/L, respectively. Levels of selenium in breast milk and serum were deficient for more than half of the lactating mothers. No statistically significant associations were found between breast milk selenium concentration and time postpartum as well as maternal diet except for eggs (r = 0.23, p = 0.01). Conclusion: The evidence of deficient concentrations of breast milk selenium indicates a poor correlation with maternal diet and suggests the need for postpartum screening of breastfeeding mothers.

Evaluation of drinking water quality using heavy metal pollution indexing models in an agrarian, non-industrialised area of South-East Nigeria.

The objectives of this study were to evaluate the physicochemical properties of drinking water sources at Ihiala, Nigeria, and to assess the water quality using the heavy metal pollution index, heavy metal evaluation index and contamination index models. Physicochemical parameters like pH, total hardness, total dissolved solids, nitrate, cyanide, residual chlorine and six metals (Al, Cd, Cr, Cu, Pb and Ni) were analyzed in the water samples, and heavy metal pollution indices computed. The spring and borehole waters had better organoleptic properties compared to stream, river and sachet waters. Total hardness, pH and nitrate were the major nonmetallic contributors to the poor water quality. The mean pollution indices were: heavy metal pollution index (HPI) 143.02 ± 71.16, heavy metal evaluation index (HEI) 7.53 ± 4.12 and contamination index (Cd) 1.53 ± 4.12. Sixty percent of the samples exceeded the critical HPI value of 100. There was significant (P < 0.01) positive correlation between HPI and Cd, HPI and HEI (r = 0.886) and HEI and Cd (r = 1.000). Lead contributed most to heavy metal pollution of water in the region. The quality of most water sources in Ihiala is not good for drinking.

Urinary excretion of rifampicin in the presence of ciprofloxacin.

To investigate the effect of the ciprofloxacin on the urinary excretion of the rifampicin in humans, ciprofloxacin and rifampicin were coadministered. Five healthy volunteers between the ages of 20 and 35 years received, on 2 separate occasions (phases 1 and 2) and at weekly intervals, 600 mg rifampicin and 600 mg plus 500 mg ciprofloxacin, respectively, with 350 mL of water. Urinary levels of rifampicin were measured from 1-72 hours later. In phase 1, 15.6% urinary rifampicin was recovered compared with 15.5% urinary rifampicin recovered in the second phase. An increased excretion rate and higher plateau were obtained in ciprofloxacin plus rifampicin treatment. The study indicates that rifampicin may be coadministered with ciprofloxacin to check the development of drug resistance to single-drug therapy by susceptible organisms.

Effect of pefloxacin on the urinary excretion of rifampicin.

The effect of pefloxacin on the urinary excretion of rifampicin was investigated in 5 healthy volunteers between the ages of 20 and 35 years. The investigation was carried out in 2 different phases, with a 1-week drug washout separating the phases. Each subject received 600 mg rifampicin with 350 mL of water. After 1 week, the subjects were given 600 mg rifampicin plus 500 mg pefloxacin with 350 mL of water. Urinary levels of rifampicin were measured spectrophotometrically for the 2 phases from 0 to 72 hours. Coadministration of rifampicin with pefloxacin led to 20.1% urinary recovery of rifampicin. The increased rifampicin excretion rate following pefloxacin coadministration is supported by the competitive liver clearance between rifampicin and pefloxacin, which favors pefloxacin and causes rifampicin secretion, thus increasing its elimination through the kidney. Pefloxacin increases the absorption and urinary excretion of rifampicin by decreasing the gastrointestinal motility through chelation mechanisms.

Nephrotoxic actions of low-dose mercury in mice: protection by zinc.

The authors conducted this study to determine if very-low-dose (i.e., 4 ppm) mercury is nephrotoxic and, if so, whether the nephrotoxic actions of mercury in mice could be prevented by zinc intake. Animals were administered 4 ppm mercuric chloride and/or 800 ppm zinc chloride in their drinking water for 12 wk. The animals were sacrificed at the end of the exposure period, and their kidneys were excised, weighed, and processed for histological study. Both metals reduced significantly (p < .05) the absolute and relative kidney weights of the animals. Zinc-treated animals showed normal kidney histology that was comparable with that of the control. Mercury treatment produced necrosis and widening of the glomeruli, whereas a combination of both metals resulted in protection from the toxic effects, with most nephrons resembling the control. The results indicate that low-dose mercury exposure in mice kidney induces some degenerative effects, which are prevented by zinc.