The pyrimidine nucleoside uridine has recently been reported to have a protective effect on cultured human corneal epithelial cells, in an animal model of dry eye and in patients. In this study, we investigate the pharmacokinetic profile of uridine in rabbits, following topical ocular (8 mg/eye), oral (450 mg/kg) and intravenous (100 mg/kg) administration. Blood and urine samples were serially taken, and uridine was measured by high-performance liquid chromatography-tandem mass spectrometry. No symptoms were noted in the animals after uridine treatment. Uridine was not detected in either plasma or urine after topical ocular administration, indicating no systemic exposure to uridine with this treatment route. Following a single intravenous dose, the plasma concentration of uridine showed a bi-exponential decay, with a rapid decline over 10 min, followed by a slow decay with a terminal half-life of 0.36 +/- 0.05 h. Clearance and volume of distribution were 1.8 +/- 0.6 L/h/kg and 0.58 +/- 0.32 L/kg, respectively. The area under the plasma concentration-time curves (AUC) was 59.7 +/- 18.2microg.hr/ml, and urinary excretion up to 12 hr was ~7.7% of the dose. Plasma uridine reached a peak of 25.8 +/- 4.1 microg/ml at 2.3 +/- 0.8 hr after oral administration. The AUC was 79.0 +/- 13.9 microg.hr/ml, representing ~29.4% of absolute bioavailability. About 1% of the oral dose was excreted in the urine. These results should prove useful in the design of future clinical and nonclinical studies conducted with uridine.
Administration, Intravenous* ; Administration, Ophthalmic ; Administration, Oral ; Animals ; Area Under Curve ; Biological Availability ; Epithelial Cells ; Half-Life ; Humans ; Mass Spectrometry ; Models, Animal ; Pharmacokinetics* ; Plasma ; Rabbits* ; Uridine*

We designed a randomized, double blinded, 3-months controlled prospective clinical study to investigate effects of oral uridine on the ocular surface in dry eye patients. Twenty-seven patients who diagnosed as dry eye with lower than 5 mm of wetting in the Schirmer strip, with corneal epithelial erosion and who completely followed-up till 3 months were enrolled. Corneal-conjunctival fluorescein staining, non-anesthetic Schirmer test, impression cytology, and Ocular Surface Disease Index (OSDI) were evaluated in the experimental and placebo groups at the baseline, 1 and 3 months after start of medication in a double blinded manner. Fluorescein stain score of the cornea was markedly decreased in oral uridine group compared to the placebo group at 3 months after medication (P=0.032, Mann-Whitney U test). The Schirmer wetting score for the oral uridine group was significantly increased (P=0.001, Wilcoxon signed rank test) at 3 months and its difference between two groups was statistically significant (P=0.030, Mann-Whitney U test). OSDI scores were significantly decreased at 1 and 3 months in treatment group. Oral uridine is effective in treatment of dry eyes.
Administration, Oral ; Adolescent ; Adult ; Aged ; Conjunctiva/pathology ; Cornea/pathology ; Double-Blind Method ; Dry Eye Syndromes/*drug therapy ; Female ; Fluorescent Dyes/pharmacology ; Humans ; Male ; Middle Aged ; Severity of Illness Index ; Uridine/administration & dosage/*therapeutic use

OBJECTIVETo develop the chromatographic fingerprints of composite Folii Isatidis injection by HPLC.

METHODThe separation was performed on a Diamonsil C18 column with a mobile phase consisting of methanol-water-phosphoric acid as gradient eluent at the flow rate of 1.0 mL x min(-1). The UV detection was set at 254 nm.

RESULTA standard HPLC fingerprint procedure was developed for composite Folii Isatidis injection, with 20 common peaks and a similarity threshold of 9.0 established.

CONCLUSIONThis method was accurate, repeatable and useful for the quality control of composite Folii Isatidis injection.

Chromatography, High Pressure Liquid ; methods ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; isolation & purification ; Ginkgo biloba ; chemistry ; Injections ; Isatis ; chemistry ; Plant Leaves ; chemistry ; Plants, Medicinal ; chemistry ; Quality Control ; Reproducibility of Results ; Uridine ; analysis

OBJECTIVETo observe the effects of combined treatment with sansanmycin and macrolides on Pseudomonas aeruginosa and formation of biofilm.

METHODSMicro-dilution method was used to determine the minimal inhibitory concentrations (MICs) of sansanmycin, gentamycin, carbenicillin, polymyxin B, roxithromycin, piperacillin, and tazobactam. PA1 and PA27853 biofilms were observed under optical microscope after staining and under SEM after treatment with sansanmycin at different dosages and combined treatment with sansanmycin and roxithromycin. Viable bacteria in PA1 and PA27853 biofilms were counted after treatment with sansanmycin at different dosages or combined treatment with sansanmycin and roxithromycin.

RESULTSThe MIC of sansanmycin was lower than that of gentamycin and polymyxin B, but was higher than that of carbenicillin. Roxithromycin enhanced the penetration of sansanmycin to PA1 and PA27853 strains through biofilms. PA1 and PA27853 biofilms were gradually cleared with the increased dosages of sansanmycin or with the combined sansanmycin and roxithromycin.

CONCLUSIONSub-MIC levels of roxithromycin and sansanmycin substantially inhibit the generation of biofilms and proliferation of bacteria. Therefore, combined antibiotics can be used in treatment of intractable bacterial infection.

Animals ; Anti-Bacterial Agents ; administration & dosage ; pharmacology ; Bacterial Adhesion ; drug effects ; Biofilms ; growth & development ; Cercopithecus aethiops ; Drug Therapy, Combination ; Macrolides ; administration & dosage ; pharmacology ; Microbial Sensitivity Tests ; Oligopeptides ; administration & dosage ; pharmacology ; Pseudomonas aeruginosa ; drug effects ; physiology ; ultrastructure ; Uridine ; administration & dosage ; analogs & derivatives ; pharmacology ; Vero Cells

OBJECTIVETo evaluate pathologically the effect of the single or combined application of UDP-glucose, GDNF and memantine on the improvement of white matter injury in neonatal rats with periventricular leukomalacia (PVL) under light and electron microscopy.

METHODSA five-day-old neonatal rat model for PVL was established by ligation of the lateral common carotid artery following 120-minute hypoxia. Rats were randomly divided into six groups (30 rats in each group): sham-operated, PVL, UDP-glucose (UDP-glucose 2000 mg/kg intraperitoneally after PVL), GDNF (GDNF 100 μg/kg intracerebrally after PVL), tmemantine (memantine 20 mg/kg intraperitoneally after PVL), and a combination administration of three drugs (UDP-glucose, GDNF and memantine). The rats were sacrificed 7 or 21 days after PVL for assessment of pathological changes in the white matter under both light and electron microscopy. The number and thickness of the myelin sheath in the white matter were measured under electron microscopy, and both of pathological grading and scoring were undertaken under light microscopy.

RESULTSThere was rare and sparse myelinogenesis with a loose arrangement of nerve fibers in the white matter under electron microscopy in the PVL group at 7 and 21 days after PVL. The number and thickness of the myelin sheath in the PVL group were significantly less than in the sham-operated, UDP-glucose, GDNF, memantine and combination administration groups (P<0.01). The results of pathological grading of white matter under light microscopy showed that all rats in the PVL group manifested either mild injury (38%-50%) or severe injury (50%-62%) at 7 and 21 days after PVL. The majority of rats (50%-88%) in the four drug administration groups had normal white matter at 7 and 21 days after PVL. The pathological scores at 7 and 21 days after PVL in the PVL group were the highest, and they were significantly higher than in the other five groups (P<0.05).

CONCLUSIONSThe single or combined application of UDP-glucose, GDNF and memantine may significantly improve pathological changes in the white matter of rats with PVL. The favorable effect is inferred to be closely correlated with the improvement of brain microenvironment and the enhancement of nerve regeneration promoted by the three drugs.

Animals ; Brain Ischemia ; drug therapy ; pathology ; Cerebral Ventricles ; pathology ; ultrastructure ; Female ; Glial Cell Line-Derived Neurotrophic Factor ; administration & dosage ; therapeutic use ; Humans ; Infant, Newborn ; Leukomalacia, Periventricular ; drug therapy ; Male ; Memantine ; administration & dosage ; therapeutic use ; Microscopy, Electron ; Rats ; Rats, Sprague-Dawley ; Uridine Diphosphate Glucose ; administration & dosage ; therapeutic use