There was a good concordance between the results of TINIA and HPLC methods (y = 1.091x - 0.363; r(2) = 0.96).

No abstract

The aim of this study was to examine some biochemical markers of bone metabolism such as C-telopeptide of type 1 collagen (CTx), procollagen I N-peptide (PINP), 25 hydroxy vitamin D [25(OH)D], parathormone (PTH), and alkaline phosphatase (total- and bone-ALP) in postmenopausal Turkish women, and to evaluate the influence of dietary factors on these parameters. This cross-sectional study comprised 70 postmenopausal and 25 premenopausal subjects from a similar socio-economical status. The postmenopausal group was further stratified with regard to vitamin plus calcium supplementation. A fasting blood sample was obtained for the biochemical analysis of bone markers. Ca, P, tALP, and CTx levels were significantly higher in postmenopausal women free of supplementation than those in premenopausal period; whereas 25(OH)D concentrations were below the reference value in both groups. Supplementations of vitamin and calcium resulted in significantly lower levels of PINP in the postmenopausal group (p = 0.017). A significant association was found between plasma 25(OH)D level and frequency of fish consumption. Dietary strategies to fortify calcium and vitamin D intake should be considered to decrease the complications due to D hypovitaminosis after the onset of menopause.

Increased oxidative stress and disturbance in nitric oxide bioavailability lead to endothelial dysfunction and cardiovascular complication in renal disease. Gentamicin (GM), a commonly used antibiotic exhibits a toxic effect on renal proximal tubules. Prevention of its nephrotoxicity is important. Therefore, we investigated whether heme oxygenase (HO)-1 induction influenced kidney and vascular function in GM-administered rats. GM (100 mg/kg/day; ip) was given to rats alone or together with hemin (20 mg/kg/alternate days; ip.) for 14 days. Plasma and kidney L-arginine, asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) as well as kidney 4-hydroxynonenal (HNE) levels and myeloperoxidase (MPO) activity were measured. Histopathologic examinations of kidney and relaxation and contraction responses of aorta were also examined.GM increased serum SDMA, urea nitrogen (BUN), and creatinine levels and caused histopathologic alterations in kidney. GM elevated HO-1 protein and mRNA expressions, 4-HNE level, MPO activity and decreased antioxidant enzyme activities and L-arginine levels in kidney. Decreased relaxation and contraction were detected in the aorta. Hemin restored renal oxidative stress and inflammatory changes together with vascular dysfunction, but did not affect SDMA, BUN, and creatinine levels. It is concluded that HO-1 induction may be effective in improving renal oxidative stress, inflammation and vascular dysfunction mediated by GM.