Studies on Free Radical EPR,Superoxide Dismutase Water-soluble Lipidperoxide in Tears

By means of electron paramagnetic resonance(EPR), chemistry luminescence and fluorescent spectroscopy, the free radical, superoxide dismutase and water soluble lipid peroxide in tears of normal eyes(150 eyes, 100 cases), Moorens ulcer(9 eyes), coreal grafts rejection(16 eyes) were studied. The results showed that the spin density of the free radical was 36(±058)×1012 spins/mL tear, the content of the superoxide dismutase(SOD) was 384(±145) ng/mL tear, the opposite fluorescent density of the water soluble lipid peroxide was 12912(±1691) U/mL tear in normal tears. The normal values are 25—48×1012 spins/mL tear for free radical, 239—529 ng/mL tear for SOD, 9598—16225 U/mL tear for water soluble lipid peroxide. There are significant differences in different eyes, different sexes and different ages. The free radical and lipid peroxide are higher obviously in the tears of patients with Moorens ulcer and rejected corneal grafts, compared with those of the normal control subjects(P<001), SOD is lower evidently(P<001). The above fact shows the pathogenic mechanism of Moorens ulcer and keractoplasty rejection is significantly related to toxicities injuring effect of the free radical. These results have provided important experimental data for studying lacrimalogy and new methods for clinical diagnosis and treatrment.

X-Linked Dominant Congenital Ptosis Cosegregating with an Interstitial Insertion of a Chromosome 1p21.3 Fragment into a Quasipalindromic Sequence in Xq27.1

Blepharoptosis (ptosis) is defined as the abnormal drooping of the upper eyelid and is a feature of many conditions. It can be in isolated or syndromic form, bilateral or unilateral and congenital or acquired. Previously we have carried out linkage analysis on a family with dominantly inherited congenital bilateral isolated ptosis and found the condition to be linked to a region of approximately 20 megabases of chromosome Xq24-Xq27.1 with a cumulative LOD score of 5.89. We now describe further analysis using array comparative genomic hybridisation (array CGH), fluorescence in situ hybridisation (FISH), long range PCR and sequencing. This has enabled us to identify and characterise at the level of DNA sequence an insertional duplication and rearrangement involving chromosomes 1p21.3 and a small quasipalindromic sequence in Xq27.1, disruption of which has been associated with other phenotypes but which is cosegregating with X-linked congenital bilateral isolated ptosis in this family. This work highlights the significance of the small quasipalindromic sequence in genomic rearrangements involving Xq27.1 and the importance of comprehensive molecular and molecular cytogenetic investigations to fully characterise genomic structural complexity.

Comparative Oral Absorption of Different Citicoline and Homotaurine Formulations: A Single-Dose, Two-Period Crossover Trial in the Dog

Background: Citicoline and homotaurine are compounds with a potent neuroprotective activity and they have been administered for many years in the treatment of numerous neurodegenerative and ophthalmological diseases, including glaucoma. Initially available only as liquid form, through parenteral route, nowadays citicoline can be administered also as tablet but no data on bioavailability of these different forms are available. In the present study, pharmacokinetics of citicoline in tablet versus vials, each at the therapeutic dose of 500 mg, in addition to 50 mg of homotaurine was investigated. Materials and methods: Ten mixed breed dogs received a single dose of 50 mg oral homotaurine and 500 mg citicoline in tablet and vials with the same dose were administered after a seven days wash-out period. Parameters assessed for citicoline metabolites (cytidine, uridine and choline) were AUC0&#8722;t, Cmax and Tmax. Results: Citicoline bioavailability appeared to be slightly higher for the tablet compared to the vial formulation. Cytidine is equivalent in absorption dynamics both for tablet and liquid form;uridine for tablet reaches its maximum and is reabsorbed more quickly while choline for the liquid form reaches the maximum first and is reabsorbed more quickly. Conclusions: Citicoline in tablet and liquid formulation have pharmacokinetic properties leading to a very similar bioavailability.