Quantitative evaluation of sparfloxacin binding to urological catheter surfaces.

Our aim was to apply high-performance liquid chromatography method for quantitative evaluation of the total amount of sparfloxacin (SPA) immobilized on the surface of the antimicrobial urological catheters. The amounts of SPA bound to catheter were determined indirectly on the basis of the differences in SPA concentrations before and after the immobilization process (they have been shown to vary from 0.11 to 5.66 mg/g of catheter). We estimated the immobilization yield, which altered from 14% to 70% depending on the SPA concentration used. As in vitro release studies show, the antibiotic binds to the catheter matrix in two modes: relatively stable covalent bond and weak non-covalent bond. Antibacterial activity of the modified catheter samples with SPA was controlledby using the zone of inhibition test against gram positive and gram negative bacteria.

Tumor necrosis factor alpha and its soluble receptors in obese children with NAFLD.

PURPOSE: To evaluate the serum levels of tumor necrosis factor (TNF) alpha and its soluble receptors in obese children with non-alcoholic fatty liver disease (NAFLD). MATERIAL/METHODS: Fasting serum levels of TNFalpha and its receptors were determined in 45 consecutive obese children with suspected liver disease and 20 lean controls. The degree of liver steatosis was graded in ultrasound according to Saverymuttu. 1H-MR spectroscopy was performed with 1.5T scanner with PRESS sequence. RESULTS: A fatty liver was confrmed in 32 children by ultrasonography (group I); 16 of them also had increased ALT activity (group Ia - NAFLD). Serum concentrations of TNFalpha and its receptors were significantly higher in obese children with NAFLD compared to controls. Significant correlation was found between ultrasonographic grade of liver steatosis and TNFalpha level but serum level of this adipokine was not significantly different in children with advanced liver steatosis (grade 2-3, n=13) compared to patients with mild steatosis (grade 1, n=19). The ability of TNFalpha and its receptors (R1, R2) to differentiate children with advanced liver steatosis from those with mild steatosis was insignificant. However, the ability of serum TNFalpha to differentiate obese children with liver steatosis from those without steatosis was significant (AUC=0.7448, p=0.0291). CONCLUSION: Although TNFalpha does not predict advanced liver steatosis, it may be suitable serum marker in predicting liver steatosis in obese children.

Application of derivative UV spectrophotometry for the determination of enoxacin and nalidixic acid in tablets.

First-, second-, third- and forth-order derivative spectrophotometric methods, using "peak-zero" (P-O) and "peak-peak" (P-P) techniques of measurement have been developed for the determination of enoxacin and nalidixic acid in tablets. The calibration curves were linear in the concentration range of 2.0-12.0 micrograms ml-1 for the analysed quinolones. The procedure was simple, rapid and the results were reliable.

Application of derivative UV spectrophotometry for the determination of ciprofloxacin, norfloxacin and ofloxacin in tablets.

The first-, second-, third- and fourth-order derivative spectrophotometric methods, by using the "peak-zero" (P-0) and "peak-peak" (P-P) techniques of measurement have been developed for the determination of ciprofloxacin hydrochloride, norfloxacin and ofloxacin in tablets. The calibration curves are linear within the concentration range of 2.0-12.0 micrograms ml-1 for ciprofloxacin hydrochloride, 1.0-10.0 micrograms ml-1 for norfloxacin and 2.5-15.0 micrograms ml-1 for ofloxacin. The procedure is simple, rapid and the results are reliable.